diff --git a/aws-iot-device-sdk-python-master/AWSIoTPythonSDK/core/protocol/paho/client.py b/aws-iot-device-sdk-python-master/AWSIoTPythonSDK/core/protocol/paho/client.py
index 503d1c6..f7c0301 100755
--- a/aws-iot-device-sdk-python-master/AWSIoTPythonSDK/core/protocol/paho/client.py
+++ b/aws-iot-device-sdk-python-master/AWSIoTPythonSDK/core/protocol/paho/client.py
@@ -1710,7 +1710,7 @@ def _topic_wildcard_len_check(self, topic):
         # Search for + or # in a topic. Return MQTT_ERR_INVAL if found.
          # Also returns MQTT_ERR_INVAL if the topic string is too long.
          # Returns MQTT_ERR_SUCCESS if everything is fine.
-        if '+' in topic or '#' in topic or len(topic) == 0 or len(topic) > 65535:
+        if not topic or '+' in topic or '#' in topic or len(topic) > 65535:
             return MQTT_ERR_INVAL
         else:
             return MQTT_ERR_SUCCESS