diff --git a/android-client/Audio_usage_license.txt b/android-client/Audio_usage_license.txt
new file mode 100644
index 0000000..10795ca
--- /dev/null
+++ b/android-client/Audio_usage_license.txt
@@ -0,0 +1,20 @@
+作品：Notification sound effects
+来源：ear0
+作者：Risteard
+许可：CC-BY 保留署名许可协议
+描述：通知铃声。
+-------------------------------------------------
+作品：load
+来源：ear0
+作者：weidu27
+许可：CC0 公众共享许可协议
+描述：叮咚
+-------------------------------------------------
+作品：nameit5
+来源：Freesound
+作者：bumpelsnake
+许可：CC-BY 保留署名许可协议
+描述：some chime, maybe a notification sound
+-------------------------------------------------
+Thank you to all the creators mentioned above.
+感谢上述所有创作者。
diff --git a/android-client/app/build.gradle.kts b/android-client/app/build.gradle.kts
index d40f9af..df2b5e5 100644
--- a/android-client/app/build.gradle.kts
+++ b/android-client/app/build.gradle.kts
@@ -14,7 +14,7 @@ android {
         minSdk = 26
         targetSdk = 34
         versionCode = 1
-        versionName = "1.0.0.2"
+        versionName = "1.0.0.3"
 
         testInstrumentationRunner = "androidx.test.runner.AndroidJUnitRunner"
         vectorDrawables {
diff --git a/android-client/app/src/main/java/com/onlinemsg/client/data/preferences/UserPreferencesRepository.kt b/android-client/app/src/main/java/com/onlinemsg/client/data/preferences/UserPreferencesRepository.kt
index 9e7974b..2394210 100644
--- a/android-client/app/src/main/java/com/onlinemsg/client/data/preferences/UserPreferencesRepository.kt
+++ b/android-client/app/src/main/java/com/onlinemsg/client/data/preferences/UserPreferencesRepository.kt
@@ -24,7 +24,8 @@ data class UserPreferences(
     val shouldAutoReconnect: Boolean,
     val themeId: String = "blue",
     val useDynamicColor: Boolean = true,
-    val language: String = "zh" // 默认中文
+    val language: String = "zh",
+    val notificationSound: String = "default"
 )
 
 class UserPreferencesRepository(
@@ -50,7 +51,8 @@ class UserPreferencesRepository(
             shouldAutoReconnect = prefs[KEY_SHOULD_AUTO_RECONNECT] ?: false,
             themeId = prefs[KEY_THEME_ID] ?: "blue",
             useDynamicColor = prefs[KEY_USE_DYNAMIC_COLOR] ?: true,
-            language = prefs[KEY_LANGUAGE] ?: "zh"
+            language = prefs[KEY_LANGUAGE] ?: "zh",
+            notificationSound = prefs[KEY_NOTIFICATION_SOUND] ?: "default"
         )
     }
 
@@ -66,6 +68,12 @@ class UserPreferencesRepository(
         }
     }
 
+    suspend fun setNotificationSound(sound: String) {
+        context.dataStore.edit { prefs ->
+            prefs[KEY_NOTIFICATION_SOUND] = sound
+        }
+    }
+
     suspend fun setUseDynamicColor(enabled: Boolean) {
         context.dataStore.edit { prefs ->
             prefs[KEY_USE_DYNAMIC_COLOR] = enabled
@@ -155,5 +163,6 @@ class UserPreferencesRepository(
         val KEY_THEME_ID: Preferences.Key<String> = stringPreferencesKey("theme_id")
         val KEY_USE_DYNAMIC_COLOR: Preferences.Key<Boolean> = booleanPreferencesKey("use_dynamic_color")
         val KEY_LANGUAGE: Preferences.Key<String> = stringPreferencesKey("language")
+        val KEY_NOTIFICATION_SOUND: Preferences.Key<String> = stringPreferencesKey("notification_sound")
     }
 }
diff --git a/android-client/app/src/main/java/com/onlinemsg/client/ui/ChatScreen.kt b/android-client/app/src/main/java/com/onlinemsg/client/ui/ChatScreen.kt
index f286efd..5e3bd26 100644
--- a/android-client/app/src/main/java/com/onlinemsg/client/ui/ChatScreen.kt
+++ b/android-client/app/src/main/java/com/onlinemsg/client/ui/ChatScreen.kt
@@ -33,6 +33,7 @@ import androidx.compose.material.icons.rounded.ContentCopy
 import androidx.compose.material.icons.rounded.Forum
 import androidx.compose.material.icons.rounded.Settings
 import androidx.compose.material.icons.rounded.Language
+import androidx.compose.material.icons.rounded.MusicNote
 import androidx.compose.material3.AssistChip
 import androidx.compose.material3.Button
 import androidx.compose.material3.Card
@@ -213,7 +214,8 @@ fun OnlineMsgApp(viewModel: ChatViewModel = viewModel()) {
                         onClearMessages = viewModel::clearMessages,
                         onThemeChange = viewModel::updateTheme,
                         onUseDynamicColorChange = viewModel::updateUseDynamicColor,
-                        onLanguageChange = viewModel::updateLanguage
+                        onLanguageChange = viewModel::updateLanguage,
+                        onNotificationSoundChange = viewModel::updateNotificationSound
                     )
                 }
             }
@@ -577,6 +579,7 @@ private fun MessageItem(
  * @param onThemeChange 切换主题
  * @param onUseDynamicColorChange 切换动态颜色
  * @param onLanguageChange 切换语言
+ * @param onNotificationSoundChange 切换通知音效
  */
 @Composable
 private fun SettingsTab(
@@ -593,7 +596,8 @@ private fun SettingsTab(
     onClearMessages: () -> Unit,
     onThemeChange: (String) -> Unit,
     onUseDynamicColorChange: (Boolean) -> Unit,
-    onLanguageChange: (String) -> Unit
+    onLanguageChange: (String) -> Unit,
+    onNotificationSoundChange: (String) -> Unit
 ) {
     fun language(key: String) = LanguageManager.getString(key, state.language)
 
@@ -736,6 +740,39 @@ private fun SettingsTab(
             }
         }
 
+        item {
+            Card(modifier = settingsCardModifier) {
+                Column(
+                    modifier = settingsCardContentModifier,
+                    verticalArrangement = settingsCardContentSpacing
+                ) {
+                    Text(language("settings.notification_sound"), style = MaterialTheme.typography.titleMedium)
+                    val sounds = listOf(
+                        "default" to language("sound.default"),
+                        "ding" to language("sound.ding"),
+                        "nameit5" to language("sound.nameit5"),
+                        "wind_chime" to language("sound.wind_chime")
+                    )
+                    LazyRow(horizontalArrangement = Arrangement.spacedBy(8.dp)) {
+                        items(sounds) { (id, label) ->
+                            FilterChip(
+                                selected = state.notificationSound == id,
+                                onClick = { onNotificationSoundChange(id) },
+                                label = { Text(label) },
+                                leadingIcon = {
+                                    Icon(
+                                        Icons.Rounded.MusicNote,
+                                        contentDescription = null,
+                                        modifier = Modifier.size(16.dp)
+                                    )
+                                }
+                            )
+                        }
+                    }
+                }
+            }
+        }
+
         item {
             Card(modifier = settingsCardModifier) {
                 Column(
diff --git a/android-client/app/src/main/java/com/onlinemsg/client/ui/ChatSessionManager.kt b/android-client/app/src/main/java/com/onlinemsg/client/ui/ChatSessionManager.kt
index 9bdec04..e65118c 100644
--- a/android-client/app/src/main/java/com/onlinemsg/client/ui/ChatSessionManager.kt
+++ b/android-client/app/src/main/java/com/onlinemsg/client/ui/ChatSessionManager.kt
@@ -5,9 +5,12 @@ import android.app.Application
 import android.app.NotificationChannel
 import android.app.NotificationManager
 import android.app.PendingIntent
+import android.content.ContentResolver
 import android.content.Context
 import android.content.Intent
 import android.content.pm.PackageManager
+import android.media.AudioAttributes
+import android.net.Uri
 import android.os.Build
 import androidx.core.app.NotificationCompat
 import androidx.core.app.NotificationManagerCompat
@@ -52,7 +55,6 @@ import com.onlinemsg.client.util.LanguageManager
 
 /**
  * 单例管理类，负责整个聊天会话的生命周期、网络连接、消息收发、状态维护和持久化。
- * 所有公开方法均通过 ViewModel 代理调用，内部使用协程处理异步操作。
  */
 object ChatSessionManager {
 
@@ -81,18 +83,18 @@ object ChatSessionManager {
     private var identity: RsaCryptoManager.Identity? = null
 
     // 连接相关内部状态
-    private var manualClose = false          // 是否为手动断开
-    private var fallbackTried = false        // 是否已尝试切换 ws/wss
-    private var connectedUrl = ""            // 当前连接的服务器地址
-    private var serverPublicKey = ""          // 服务端公钥（握手后获得）
-    private var helloTimeoutJob: Job? = null  // 握手超时任务
-    private var authTimeoutJob: Job? = null   // 认证超时任务
-    private var reconnectJob: Job? = null     // 自动重连任务
-    private var reconnectAttempt: Int = 0     // 当前重连尝试次数
-    private val systemMessageExpiryJobs: MutableMap<String, Job> = mutableMapOf() // 系统消息自动过期任务
+    private var manualClose = false
+    private var fallbackTried = false
+    private var connectedUrl = ""
+    private var serverPublicKey = ""
+    private var helloTimeoutJob: Job? = null
+    private var authTimeoutJob: Job? = null
+    private var reconnectJob: Job? = null
+    private var reconnectAttempt: Int = 0
+    private val systemMessageExpiryJobs: MutableMap<String, Job> = mutableMapOf()
     private var autoReconnectTriggered = false
     @Volatile
-    private var keepAliveRequested = false    // 是否应保活（前台服务标志）
+    private var keepAliveRequested = false
     private var notificationIdSeed = 2000
 
     // WebSocket 事件监听器
@@ -167,10 +169,6 @@ object ChatSessionManager {
         }
     }
 
-    /**
-     * 初始化管理器，必须在应用启动时调用一次。
-     * @param application Application 实例
-     */
     @Synchronized
     fun initialize(application: Application) {
         if (initialized) return
@@ -179,7 +177,6 @@ object ChatSessionManager {
         preferencesRepository = UserPreferencesRepository(application, json)
         cryptoManager = RsaCryptoManager(application)
         historyRepository = ChatHistoryRepository(ChatDatabase.getInstance(application).chatMessageDao())
-        ensureMessageNotificationChannel()
 
         scope.launch {
             val pref = preferencesRepository.preferencesFlow.first()
@@ -197,11 +194,14 @@ object ChatSessionManager {
                     themeId = pref.themeId,
                     useDynamicColor = pref.useDynamicColor,
                     language = pref.language,
+                    notificationSound = pref.notificationSound,
                     messages = historyMessages,
                     statusHint = LanguageManager.getString("status_hint.click_to_connect", pref.language)
                 )
             }
-            // 如果上次会话启用了自动重连，则自动恢复连接
+            
+            ensureMessageNotificationChannel(pref.notificationSound)
+
             if (pref.shouldAutoReconnect && !autoReconnectTriggered) {
                 autoReconnectTriggered = true
                 ChatForegroundService.start(application)
@@ -210,10 +210,14 @@ object ChatSessionManager {
         }
     }
 
-    /**
-     * 更新主题
-     * @param themeId 主题名
-     */
+    fun updateNotificationSound(sound: String) {
+        _uiState.update { it.copy(notificationSound = sound) }
+        scope.launch {
+            preferencesRepository.setNotificationSound(sound)
+            ensureMessageNotificationChannel(sound)
+        }
+    }
+
     fun updateTheme(themeId: String) {
         _uiState.update { it.copy(themeId = themeId) }
         scope.launch {
@@ -221,10 +225,6 @@ object ChatSessionManager {
         }
     }
 
-    /**
-     * 更新语言
-     * @param language 语言代码
-     */
     fun updateLanguage(language: String) {
         _uiState.update { it.copy(language = language) }
         scope.launch {
@@ -232,10 +232,6 @@ object ChatSessionManager {
         }
     }
 
-    /**
-     * 更改使用动态颜色
-     * @param enabled 主题名
-     */
     fun updateUseDynamicColor(enabled: Boolean) {
         _uiState.update { it.copy(useDynamicColor = enabled) }
         scope.launch {
@@ -243,10 +239,6 @@ object ChatSessionManager {
         }
     }
 
-    /**
-     * 更新显示名称并持久化。
-     * @param value 新名称（自动截断至 64 字符）
-     */
     fun updateDisplayName(value: String) {
         val displayName = value.take(64)
         _uiState.update { it.copy(displayName = displayName) }
@@ -255,34 +247,18 @@ object ChatSessionManager {
         }
     }
 
-    /**
-     * 更新当前输入的服务器地址（不持久化）。
-     * @param value 新地址
-     */
     fun updateServerUrl(value: String) {
         _uiState.update { it.copy(serverUrl = value) }
     }
 
-    /**
-     * 更新私聊目标公钥。
-     * @param value 公钥字符串
-     */
     fun updateTargetKey(value: String) {
         _uiState.update { it.copy(targetKey = value) }
     }
 
-    /**
-     * 更新消息草稿。
-     * @param value 草稿内容
-     */
     fun updateDraft(value: String) {
         _uiState.update { it.copy(draft = value) }
     }
 
-    /**
-     * 切换广播/私聊模式并持久化。
-     * @param enabled true 为私聊模式
-     */
     fun toggleDirectMode(enabled: Boolean) {
         _uiState.update { it.copy(directMode = enabled) }
         scope.launch {
@@ -290,10 +266,6 @@ object ChatSessionManager {
         }
     }
 
-    /**
-     * 切换是否显示系统消息并持久化。
-     * @param show true 显示
-     */
     fun toggleShowSystemMessages(show: Boolean) {
         _uiState.update { it.copy(showSystemMessages = show) }
         scope.launch {
@@ -301,9 +273,6 @@ object ChatSessionManager {
         }
     }
 
-    /**
-     * 清空所有消息，并取消系统消息的过期任务。
-     */
     fun clearMessages() {
         cancelSystemMessageExpiryJobs()
         _uiState.update { it.copy(messages = emptyList()) }
@@ -314,9 +283,6 @@ object ChatSessionManager {
         }
     }
 
-    /**
-     * 保存当前服务器地址到历史列表并持久化。
-     */
     fun saveCurrentServerUrl() {
         val normalized = ServerUrlFormatter.normalize(_uiState.value.serverUrl)
         if (normalized.isBlank()) {
@@ -342,10 +308,6 @@ object ChatSessionManager {
         }
     }
 
-    /**
-     * 从历史列表中移除当前服务器地址。
-     * 如果列表清空则恢复默认地址。
-     */
     fun removeCurrentServerUrl() {
         val normalized = ServerUrlFormatter.normalize(_uiState.value.serverUrl)
         if (normalized.isBlank()) return
@@ -376,9 +338,6 @@ object ChatSessionManager {
         }
     }
 
-    /**
-     * 加载或生成本地身份密钥对，并将公钥显示到 UI。
-     */
     fun revealMyPublicKey() {
         scope.launch {
             _uiState.update { it.copy(loadingPublicKey = true) }
@@ -398,17 +357,10 @@ object ChatSessionManager {
         }
     }
 
-    /**
-     * 主动连接服务器（由用户点击连接触发）。
-     */
     fun connect() {
         connectInternal(isAutoRestore = false)
     }
 
-    /**
-     * 内部连接逻辑，区分自动恢复和手动连接。
-     * @param isAutoRestore 是否为应用启动时的自动恢复连接
-     */
     private fun connectInternal(isAutoRestore: Boolean) {
         if (!initialized) return
         val state = _uiState.value
@@ -459,10 +411,6 @@ object ChatSessionManager {
         }
     }
 
-    /**
-     * 主动断开连接。
-     * @param stopService 是否同时停止前台服务（默认 true）
-     */
     fun disconnect(stopService: Boolean = true) {
         manualClose = true
         cancelReconnect()
@@ -487,10 +435,6 @@ object ChatSessionManager {
         addSystemMessage("已断开连接")
     }
 
-    /**
-     * 发送消息（广播或私聊）。
-     * 执行签名、加密并发送。
-     */
     fun sendMessage() {
         val current = _uiState.value
         if (!current.canSend) return
@@ -549,19 +493,12 @@ object ChatSessionManager {
         }
     }
 
-    /**
-     * 消息复制成功后的回调，显示“已复制”提示。
-     */
     fun onMessageCopied() {
         scope.launch {
             _events.emit(UiEvent.ShowSnackbar("已复制"))
         }
     }
 
-    /**
-     * 确保本地身份已加载 or 创建。
-     * @return 本地身份对象
-     */
     private suspend fun ensureIdentity(): RsaCryptoManager.Identity {
         return identityMutex.withLock {
             identity ?: withContext(Dispatchers.Default) {
@@ -572,10 +509,6 @@ object ChatSessionManager {
         }
     }
 
-    /**
-     * 处理收到的原始文本消息（可能是握手包 or 加密消息）。
-     * @param rawText 原始文本
-     */
     private suspend fun handleIncomingMessage(rawText: String) {
         if (_uiState.value.status == ConnectionStatus.HANDSHAKING) {
             val lang = _uiState.value.language
@@ -587,7 +520,6 @@ object ChatSessionManager {
             json.decodeFromString<JsonElement>(normalizedText) as? JsonObject
         }.getOrNull()
 
-        // 尝试直接解析为 HelloDataDto（某些服务器可能直接发送，不带外层）
         val directHello = rootObject?.let { obj ->
             val hasPublicKey = obj["publicKey"] != null
             val hasChallenge = obj["authChallenge"] != null
@@ -603,7 +535,6 @@ object ChatSessionManager {
             return
         }
 
-        // 尝试解析为带外层的 EnvelopeDto
         val plain = runCatching { json.decodeFromString<EnvelopeDto>(normalizedText) }.getOrNull()
         if (plain?.type == "publickey") {
             cancelHelloTimeout()
@@ -624,7 +555,6 @@ object ChatSessionManager {
             return
         }
 
-        // 握手阶段收到非预期消息则报错
         if (_uiState.value.status == ConnectionStatus.HANDSHAKING && plain != null) {
             val lang = _uiState.value.language
             _uiState.update { it.copy(statusHint = LanguageManager.getString("status_hint.handshake_failed_unexpected", lang)) }
@@ -636,7 +566,6 @@ object ChatSessionManager {
             addSystemMessage("握手包解析失败：$preview")
         }
 
-        // 尝试解密（若已握手完成，收到的应是加密消息）
         val id = ensureIdentity()
         val decrypted = runCatching {
             withContext(Dispatchers.Default) {
@@ -654,10 +583,6 @@ object ChatSessionManager {
         handleSecureMessage(secure)
     }
 
-    /**
-     * 处理服务端发来的握手 Hello 数据。
-     * @param hello 服务端公钥和挑战
-     */
     private suspend fun handleServerHello(hello: HelloDataDto) {
         cancelHelloTimeout()
         serverPublicKey = hello.publicKey
@@ -704,10 +629,6 @@ object ChatSessionManager {
         }
     }
 
-    /**
-     * 发送认证消息（包含签名后的身份信息）。
-     * @param challenge 服务端提供的挑战值
-     */
     private suspend fun sendAuth(challenge: String) {
         val id = ensureIdentity()
         val displayName = _uiState.value.displayName.trim().ifBlank { createGuestName() }
@@ -751,10 +672,6 @@ object ChatSessionManager {
         check(socketClient.send(cipher)) { "连接不可用" }
     }
 
-    /**
-     * 处理安全通道建立后的业务消息（广播、私聊、认证结果等）。
-     * @param message 解密后的 EnvelopeDto
-     */
     private fun handleSecureMessage(message: EnvelopeDto) {
         when (message.type) {
             "auth_ok" -> {
@@ -795,30 +712,15 @@ object ChatSessionManager {
         }
     }
 
-    /**
-     * 处理 WebSocket 连接关闭事件。
-     * @param code 关闭状态码
-     * @param reason 关闭原因
-     */
     private fun handleSocketClosed(code: Int, reason: String) {
         cancelHelloTimeout()
         cancelAuthTimeout()
 
-        if (manualClose) {
-            return
-        }
-        if (reason == "reconnect") {
-            return
-        }
-        if (reconnectJob?.isActive == true) {
-            return
-        }
+        if (manualClose || reason == "reconnect" || reconnectJob?.isActive == true) return
 
         val currentStatus = _uiState.value.status
-
         val allowFallback = !fallbackTried && currentStatus != ConnectionStatus.READY
 
-        // 尝试切换 ws/wss 协议重试（仅限非就绪状态）
         if (allowFallback) {
             val fallbackUrl = ServerUrlFormatter.toggleWsProtocol(connectedUrl)
             if (fallbackUrl.isNotBlank()) {
@@ -847,13 +749,8 @@ object ChatSessionManager {
         }
         addSystemMessage("连接关闭 ($code)：${reason.ifBlank { "连接中断" }}")
         scheduleReconnect("连接已中断")
-
     }
 
-    /**
-     * 添加一条系统消息（自动按 TTL 过期）。
-     * @param content 消息内容
-     */
     private fun addSystemMessage(content: String) {
         val message = UiMessage(
             role = MessageRole.SYSTEM,
@@ -866,13 +763,6 @@ object ChatSessionManager {
         scheduleSystemMessageExpiry(message.id)
     }
 
-    /**
-     * 添加一条接收到的用户消息。
-     * @param sender 发送者名称
-     * @param subtitle 附加说明（如私聊来源）
-     * @param content 消息内容
-     * @param channel 消息通道（广播/私聊）
-     */
     private fun addIncomingMessage(
         sender: String,
         subtitle: String,
@@ -894,12 +784,6 @@ object ChatSessionManager {
         )
     }
 
-    /**
-     * 添加一条发出的消息。
-     * @param content 消息内容
-     * @param subtitle 附加说明（如私聊目标）
-     * @param channel 消息通道
-     */
     private fun addOutgoingMessage(
         content: String,
         subtitle: String,
@@ -916,15 +800,11 @@ object ChatSessionManager {
         )
     }
 
-    /**
-     * 将消息追加到列表尾部，并清理超出数量限制的消息。
-     * @param message 要追加的消息
-     */
     private fun appendMessage(message: UiMessage) {
         _uiState.update { current ->
             val next = (current.messages + message).takeLast(MAX_MESSAGES)
             val aliveIds = next.asSequence().map { it.id }.toSet()
-            val removedIds = systemMessageExpiryJobs.keys.filterNot { it in aliveIds }
+            val removedIds = systemMessageExpiryJobs.keys.filterNot { id -> id in aliveIds }
             removedIds.forEach { id ->
                 systemMessageExpiryJobs.remove(id)?.cancel()
             }
@@ -938,21 +818,13 @@ object ChatSessionManager {
         }
     }
 
-    /**
-     * 取消认证超时任务。
-     */
     private fun cancelAuthTimeout() {
         authTimeoutJob?.cancel()
         authTimeoutJob = null
     }
 
-    /**
-     * 安排自动重连（指数退避）。
-     * @param reason 触发重连的原因
-     */
     private fun scheduleReconnect(reason: String) {
-        if (manualClose) return
-        if (reconnectJob?.isActive == true) return
+        if (manualClose || reconnectJob?.isActive == true) return
 
         reconnectAttempt += 1
         val exponential = 1 shl minOf(reconnectAttempt - 1, 5)
@@ -1004,18 +876,11 @@ object ChatSessionManager {
         }
     }
 
-    /**
-     * 取消自动重连任务。
-     */
     private fun cancelReconnect() {
         reconnectJob?.cancel()
         reconnectJob = null
     }
 
-    /**
-     * 为系统消息安排过期自动删除。
-     * @param messageId 消息唯一 ID
-     */
     private fun scheduleSystemMessageExpiry(messageId: String) {
         systemMessageExpiryJobs.remove(messageId)?.cancel()
         systemMessageExpiryJobs[messageId] = scope.launch {
@@ -1028,17 +893,11 @@ object ChatSessionManager {
         }
     }
 
-    /**
-     * 取消所有系统消息的过期任务。
-     */
     private fun cancelSystemMessageExpiryJobs() {
         systemMessageExpiryJobs.values.forEach { it.cancel() }
         systemMessageExpiryJobs.clear()
     }
 
-    /**
-     * 启动握手超时计时器。
-     */
     private fun startHelloTimeout() {
         cancelHelloTimeout()
         helloTimeoutJob = scope.launch {
@@ -1058,56 +917,29 @@ object ChatSessionManager {
         }
     }
 
-    /**
-     * 取消握手超时任务。
-     */
     private fun cancelHelloTimeout() {
         helloTimeoutJob?.cancel()
         helloTimeoutJob = null
     }
 
-    /**
-     * 缩写显示公钥（取前后各8字符）。
-     * @param key 完整公钥
-     * @return 缩写字符串
-     */
     private fun summarizeKey(key: String): String {
         if (key.length <= 16) return key
         return "${key.take(8)}...${key.takeLast(8)}"
     }
 
-    /**
-     * 生成访客名称（如 guest-123456）。
-     * @return 随机名称
-     */
     private fun createGuestName(): String {
         val rand = (100000..999999).random()
         return "guest-$rand"
     }
 
-    /**
-     * 从可能包含前缀的原始文本中提取 JSON 对象部分。
-     * @param rawText 原始文本
-     * @return 最外层的 JSON 字符串
-     */
     private fun extractJsonCandidate(rawText: String): String {
         val trimmed = rawText.trim()
-        if (trimmed.startsWith("{") && trimmed.endsWith("}")) {
-            return trimmed
-        }
-
+        if (trimmed.startsWith("{") && trimmed.endsWith("}")) return trimmed
         val start = rawText.indexOf('{')
         val end = rawText.lastIndexOf('}')
-        return if (start in 0 until end) {
-            rawText.substring(start, end + 1)
-        } else {
-            rawText
-        }
+        return if (start in 0 until end) rawText.substring(start, end + 1) else rawText
     }
 
-    /**
-     * 关闭所有资源（用于应用退出时）。
-     */
     fun shutdownAll() {
         cancelSystemMessageExpiryJobs()
         cancelReconnect()
@@ -1116,9 +948,6 @@ object ChatSessionManager {
         socketClient.shutdown()
     }
 
-    /**
-     * 前台服务停止时的回调。
-     */
     fun onForegroundServiceStopped() {
         keepAliveRequested = false
         if (_uiState.value.status != ConnectionStatus.IDLE) {
@@ -1130,52 +959,57 @@ object ChatSessionManager {
         }
     }
 
-    /**
-     * 判断前台服务是否应该运行。
-     * @return true 表示应保持服务运行
-     */
     fun shouldForegroundServiceRun(): Boolean = keepAliveRequested
 
-    /**
-     * 创建消息通知渠道（Android O+）。
-     */
-    private fun ensureMessageNotificationChannel() {
+    private fun ensureMessageNotificationChannel(soundCode: String = "default") {
         if (Build.VERSION.SDK_INT < Build.VERSION_CODES.O) return
         val manager = app.getSystemService(Context.NOTIFICATION_SERVICE) as NotificationManager
+        val channelId = "${MESSAGE_CHANNEL_ID}_$soundCode"
+        if (manager.getNotificationChannel(channelId) != null) return
+
+        val soundUri = getSoundUri(soundCode)
         val channel = NotificationChannel(
-            MESSAGE_CHANNEL_ID,
+            channelId,
             "OnlineMsg 消息提醒",
             NotificationManager.IMPORTANCE_DEFAULT
         ).apply {
             description = "收到服务器新消息时提醒"
+            if (soundUri != null) {
+                setSound(soundUri, AudioAttributes.Builder()
+                    .setUsage(AudioAttributes.USAGE_NOTIFICATION)
+                    .setContentType(AudioAttributes.CONTENT_TYPE_SONIFICATION)
+                    .build())
+            }
         }
         manager.createNotificationChannel(channel)
     }
 
-    /**
-     * 显示新消息到达的通知。
-     * @param title 通知标题
-     * @param body 通知正文
-     */
+    private fun getSoundUri(code: String): Uri? {
+        val resId = when(code) {
+            "ding" -> R.raw.load
+            "nameit5" -> R.raw.nameit5
+            "wind_chime" -> R.raw.notification_sound_effects
+            "default" -> R.raw.default_sound
+            else -> return null
+        }
+        return Uri.parse(ContentResolver.SCHEME_ANDROID_RESOURCE + "://" + app.packageName + "/" + resId)
+    }
+
     private fun showIncomingNotification(title: String, body: String) {
         if (!initialized) return
         if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.TIRAMISU &&
             ContextCompat.checkSelfPermission(app, Manifest.permission.POST_NOTIFICATIONS) != PackageManager.PERMISSION_GRANTED
-        ) {
-            return
-        }
+        ) return
 
         val launchIntent = Intent(app, MainActivity::class.java).apply {
             flags = Intent.FLAG_ACTIVITY_NEW_TASK or Intent.FLAG_ACTIVITY_CLEAR_TOP
         }
-        val pendingIntent = PendingIntent.getActivity(
-            app,
-            0,
-            launchIntent,
-            PendingIntent.FLAG_UPDATE_CURRENT or PendingIntent.FLAG_IMMUTABLE
-        )
+        val pendingIntent = PendingIntent.getActivity(app, 0, launchIntent, PendingIntent.FLAG_UPDATE_CURRENT or PendingIntent.FLAG_IMMUTABLE)
+
+        val soundCode = _uiState.value.notificationSound
+        val channelId = "${MESSAGE_CHANNEL_ID}_$soundCode"
 
-        val notification = NotificationCompat.Builder(app, MESSAGE_CHANNEL_ID)
+        val notification = NotificationCompat.Builder(app, channelId)
             .setSmallIcon(android.R.drawable.stat_notify_chat)
             .setContentTitle(title.ifBlank { "OnlineMsg" })
             .setContentText(body.take(120))
@@ -1188,17 +1022,12 @@ object ChatSessionManager {
         NotificationManagerCompat.from(app).notify(nextMessageNotificationId(), notification)
     }
 
-    /**
-     * 生成下一个通知 ID（线程安全递增）。
-     * @return 新的通知 ID
-     */
     @Synchronized
     private fun nextMessageNotificationId(): Int {
         notificationIdSeed += 1
         return notificationIdSeed
     }
 
-    // 常量定义
     private const val HELLO_TIMEOUT_MS = 12_000L
     private const val AUTH_TIMEOUT_MS = 20_000L
     private const val MAX_MESSAGES = 500
diff --git a/android-client/app/src/main/java/com/onlinemsg/client/ui/ChatUiState.kt b/android-client/app/src/main/java/com/onlinemsg/client/ui/ChatUiState.kt
index e0438ac..86f0938 100644
--- a/android-client/app/src/main/java/com/onlinemsg/client/ui/ChatUiState.kt
+++ b/android-client/app/src/main/java/com/onlinemsg/client/ui/ChatUiState.kt
@@ -70,7 +70,10 @@ data class UiMessage(
  * @property myPublicKey 本地公钥
  * @property sending 是否正在发送消息（用于禁用按钮）
  * @property loadingPublicKey 是否正在加载公钥
- * @property language 当前选择的语言代码 (如 "zh", "en", "ja")
+ * @property themeId 当前选中的主题 ID
+ * @property useDynamicColor 是否使用 Android 12+ 动态颜色
+ * @property language 当前选择的语言代码
+ * @property notificationSound 当前选择的通知音效代号
  */
 data class ChatUiState(
     val status: ConnectionStatus = ConnectionStatus.IDLE,
@@ -89,7 +92,8 @@ data class ChatUiState(
     val loadingPublicKey: Boolean = false,
     val themeId: String = "blue",
     val useDynamicColor: Boolean = true,
-    val language: String = "zh"
+    val language: String = "zh",
+    val notificationSound: String = "default"
 ) {
     /**
      * 是否允许连接。
@@ -112,7 +116,6 @@ data class ChatUiState(
     val canSend: Boolean
         get() = status == ConnectionStatus.READY && draft.trim().isNotEmpty() && !sending
 
-    
     /**
      * 连接状态的简短文本描述。
      */
@@ -145,4 +148,4 @@ data class ChatUiState(
  */
 sealed interface UiEvent {
     data class ShowSnackbar(val message: String) : UiEvent
-}
\ No newline at end of file
+}
diff --git a/android-client/app/src/main/java/com/onlinemsg/client/ui/ChatViewModel.kt b/android-client/app/src/main/java/com/onlinemsg/client/ui/ChatViewModel.kt
index 8b53474..eb18399 100644
--- a/android-client/app/src/main/java/com/onlinemsg/client/ui/ChatViewModel.kt
+++ b/android-client/app/src/main/java/com/onlinemsg/client/ui/ChatViewModel.kt
@@ -35,4 +35,5 @@ class ChatViewModel(application: Application) : AndroidViewModel(application) {
     fun updateTheme(themeId: String) = ChatSessionManager.updateTheme(themeId)
     fun updateUseDynamicColor(enabled: Boolean) = ChatSessionManager.updateUseDynamicColor(enabled)
     fun updateLanguage(language: String) = ChatSessionManager.updateLanguage(language)
+    fun updateNotificationSound(sound: String) = ChatSessionManager.updateNotificationSound(sound)
 }
\ No newline at end of file
diff --git a/android-client/app/src/main/java/com/onlinemsg/client/util/LanguageManager.kt b/android-client/app/src/main/java/com/onlinemsg/client/util/LanguageManager.kt
index 40cc2bc..7328ee7 100644
--- a/android-client/app/src/main/java/com/onlinemsg/client/util/LanguageManager.kt
+++ b/android-client/app/src/main/java/com/onlinemsg/client/util/LanguageManager.kt
@@ -2,7 +2,7 @@ package com.onlinemsg.client.util
 
 /**
  * 语言管理类，统一存储应用内的多语言词条。
- * 类似于 Minecraft 的语言文件映射。
+ * 类似于 Minecraft 的 language 文件映射。
  */
 object LanguageManager {
 
@@ -32,6 +32,11 @@ object LanguageManager {
             "settings.show_system" to "显示系统消息",
             "settings.clear_msg" to "清空消息",
             "settings.dynamic_color" to "使用动态颜色",
+            "settings.notification_sound" to "通知音效",
+            "sound.default" to "默认",
+            "sound.ding" to "叮",
+            "sound.nameit5" to "音效5",
+            "sound.wind_chime" to "风铃",
             "chat.broadcast" to "广播",
             "chat.private" to "私聊",
             "chat.target_key" to "目标公钥",
@@ -101,6 +106,11 @@ object LanguageManager {
             "settings.show_system" to "Show System Messages",
             "settings.clear_msg" to "ClearMsg",
             "settings.dynamic_color" to "Use dynamic color",
+            "settings.notification_sound" to "Notification Sound",
+            "sound.default" to "Default",
+            "sound.ding" to "Ding",
+            "sound.nameit5" to "Sound 5",
+            "sound.wind_chime" to "Wind Chime",
             "chat.broadcast" to "Broadcast",
             "chat.private" to "Private",
             "chat.target_key" to "Target Public Key",
@@ -170,6 +180,11 @@ object LanguageManager {
             "settings.show_system" to "システムメッセージを表示",
             "settings.clear_msg" to "履歴を消去",
             "settings.dynamic_color" to "動的カラーを使用",
+            "settings.notification_sound" to "通知音",
+            "sound.default" to "デフォルト",
+            "sound.ding" to "ディン",
+            "sound.nameit5" to "音効5",
+            "sound.wind_chime" to "風鈴",
             "chat.broadcast" to "全体",
             "chat.private" to "個人",
             "chat.target_key" to "相手の公開鍵",
@@ -239,6 +254,11 @@ object LanguageManager {
             "settings.show_system" to "시스템 메시지 표시",
             "settings.clear_msg" to "정보 삭제",
             "settings.dynamic_color" to "동적 색상 사용",
+            "settings.notification_sound" to "알림 소리",
+            "sound.default" to "기본값",
+            "sound.ding" to "딩",
+            "sound.nameit5" to "효과음 5",
+            "sound.wind_chime" to "풍경",
             "chat.broadcast" to "브로드캐스트",
             "chat.private" to "비공개 채팅",
             "chat.target_key" to "대상 공개키",
@@ -309,6 +329,11 @@ object LanguageManager {
             "settings.show_system" to "顯示系統訊息",
             "settings.clear_msg" to "清空訊息",
             "settings.dynamic_color" to "使用動態顏色",
+            "settings.notification_sound" to "通知音效",
+            "sound.default" to "預設",
+            "sound.ding" to "叮",
+            "sound.nameit5" to "音效5",
+            "sound.wind_chime" to "風鈴",
             "chat.broadcast" to "廣播",
             "chat.private" to "私訊",
             "chat.target_key" to "目標公鑰",
diff --git a/android-client/app/src/main/res/raw/default_sound.mp3 b/android-client/app/src/main/res/raw/default_sound.mp3
new file mode 100644
index 0000000..f3a2068
Binary files /dev/null and b/android-client/app/src/main/res/raw/default_sound.mp3 differ
diff --git a/android-client/app/src/main/res/raw/load.mp3 b/android-client/app/src/main/res/raw/load.mp3
new file mode 100644
index 0000000..8afb4c6
Binary files /dev/null and b/android-client/app/src/main/res/raw/load.mp3 differ
diff --git a/android-client/app/src/main/res/raw/nameit5.wav b/android-client/app/src/main/res/raw/nameit5.wav
new file mode 100644
index 0000000..ef49ba4
Binary files /dev/null and b/android-client/app/src/main/res/raw/nameit5.wav differ
diff --git a/android-client/app/src/main/res/raw/notification_sound_effects.mp3 b/android-client/app/src/main/res/raw/notification_sound_effects.mp3
new file mode 100644
index 0000000..54402ab
Binary files /dev/null and b/android-client/app/src/main/res/raw/notification_sound_effects.mp3 differ