diff --git a/AWSIoT/Internal/AWSIoTMQTTClient.m b/AWSIoT/Internal/AWSIoTMQTTClient.m
index 010a2df956f..96df6717e36 100644
--- a/AWSIoT/Internal/AWSIoTMQTTClient.m
+++ b/AWSIoT/Internal/AWSIoTMQTTClient.m
@@ -690,12 +690,19 @@ - (void)cleanupReconnectTimer {
                     waitUntilDone:NO];
             return;
         }
-        
-        [self.reconnectTimer invalidate];
-        self.reconnectTimer = nil;
+
+        [self invalidateReconnectTimer];
     }
 }
 
+- (void)invalidateReconnectTimer {
+    __weak AWSIoTMQTTClient *weakSelf = self;
+    dispatch_async(self.timerQueue, ^{
+        [weakSelf.reconnectTimer invalidate];
+        weakSelf.reconnectTimer = nil;
+    });
+}
+
 - (void)cleanUpWebsocketOutputStream {
     @synchronized(self) {
         if (self.websocketOutputStream) {
diff --git a/CHANGELOG.md b/CHANGELOG.md
index d3cd754a609..3ac61be687e 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,7 +2,10 @@
 
 ## Unreleased
 
--Features for next release
+### Bug Fixes
+
+- **AWSIoT** 
+  - Fixing a race condition when invalidating/creating the reconnect timer (#5454)
 
 ## 2.38.0