diff --git a/mirai-core-qqandroid/src/commonMain/kotlin/net/mamoe/mirai/qqandroid/network/QQAndroidBotNetworkHandler.kt b/mirai-core-qqandroid/src/commonMain/kotlin/net/mamoe/mirai/qqandroid/network/QQAndroidBotNetworkHandler.kt
index af8165357..4746a5fff 100644
--- a/mirai-core-qqandroid/src/commonMain/kotlin/net/mamoe/mirai/qqandroid/network/QQAndroidBotNetworkHandler.kt
+++ b/mirai-core-qqandroid/src/commonMain/kotlin/net/mamoe/mirai/qqandroid/network/QQAndroidBotNetworkHandler.kt
@@ -76,7 +76,7 @@ internal class QQAndroidBotNetworkHandler(bot: QQAndroidBot) : BotNetworkHandler
                     return@launch
                 } catch (e: Throwable) {
                     if (this@QQAndroidBotNetworkHandler.isActive) {
-                        BotOfflineEvent.Dropped(bot).broadcast()
+                        BotOfflineEvent.Dropped(bot, e).broadcast()
                     }
                     return@launch
                 }
@@ -96,15 +96,15 @@ internal class QQAndroidBotNetworkHandler(bot: QQAndroidBot) : BotNetworkHandler
                 val failException = doHeartBeat()
                 if (failException != null) {
                     delay(bot.configuration.firstReconnectDelayMillis)
-                    close()
-                    BotOfflineEvent.Dropped(bot).broadcast()
+                    close(failException)
+                    BotOfflineEvent.Dropped(bot, failException).broadcast()
                 }
             }
         }.also { heartbeatJob = it }
     }
 
-    override suspend fun relogin() {
-        heartbeatJob?.cancel(CancellationException("relogin"))
+    override suspend fun relogin(cause: Throwable?) {
+        heartbeatJob?.cancel(CancellationException("relogin", cause))
         if (::channel.isInitialized) {
             if (channel.isOpen) {
                 kotlin.runCatching {
@@ -119,7 +119,7 @@ internal class QQAndroidBotNetworkHandler(bot: QQAndroidBot) : BotNetworkHandler
         withTimeoutOrNull(3000) {
             channel.connect("113.96.13.208", 8080)
         } ?: error("timeout connecting server")
-        startPacketReceiverJobOrKill(CancellationException("reconnect"))
+        startPacketReceiverJobOrKill(CancellationException("relogin", cause))
 
         var response: WtLogin.Login.LoginPacketResponse = WtLogin.Login.SubCommand9(bot.client).sendAndExpect()
         mainloop@ while (true) {
diff --git a/mirai-core/src/commonMain/kotlin/net.mamoe.mirai/BotImpl.kt b/mirai-core/src/commonMain/kotlin/net.mamoe.mirai/BotImpl.kt
index 66ffdd235..4f6fc0f8a 100644
--- a/mirai-core/src/commonMain/kotlin/net.mamoe.mirai/BotImpl.kt
+++ b/mirai-core/src/commonMain/kotlin/net.mamoe.mirai/BotImpl.kt
@@ -92,7 +92,7 @@ abstract class BotImpl<N : BotNetworkHandler> constructor(
                     if (tryCount != 0) {
                         delay(configuration.reconnectPeriodMillis)
                     }
-                    network.relogin()
+                    network.relogin(event.cause)
                     logger.info("Reconnected successfully")
                     return@subscribeAlways
                 }?.let {
diff --git a/mirai-core/src/commonMain/kotlin/net.mamoe.mirai/event/events/BotEvents.kt b/mirai-core/src/commonMain/kotlin/net.mamoe.mirai/event/events/BotEvents.kt
index a855e40b2..0deab64d0 100644
--- a/mirai-core/src/commonMain/kotlin/net.mamoe.mirai/event/events/BotEvents.kt
+++ b/mirai-core/src/commonMain/kotlin/net.mamoe.mirai/event/events/BotEvents.kt
@@ -57,7 +57,7 @@ sealed class BotOfflineEvent : BotEvent {
     /**
      * 被服务器断开或因网络问题而掉线
      */
-    data class Dropped(override val bot: Bot) : BotOfflineEvent(), Packet, BotPassiveEvent
+    data class Dropped(override val bot: Bot, val cause: Throwable?) : BotOfflineEvent(), Packet, BotPassiveEvent
 }
 
 /**
diff --git a/mirai-core/src/commonMain/kotlin/net.mamoe.mirai/network/BotNetworkHandler.kt b/mirai-core/src/commonMain/kotlin/net.mamoe.mirai/network/BotNetworkHandler.kt
index 66e4a544e..b2f36d33b 100644
--- a/mirai-core/src/commonMain/kotlin/net.mamoe.mirai/network/BotNetworkHandler.kt
+++ b/mirai-core/src/commonMain/kotlin/net.mamoe.mirai/network/BotNetworkHandler.kt
@@ -68,7 +68,7 @@ abstract class BotNetworkHandler : CoroutineScope {
      */
     @Suppress("SpellCheckingInspection")
     @MiraiInternalAPI
-    abstract suspend fun relogin()
+    abstract suspend fun relogin(cause: Throwable? = null)
 
     /**
      * 初始化获取好友列表等值.