diff --git a/clickhouse_driver/connection.py b/clickhouse_driver/connection.py
index 9255774..7ec2aa2 100644
--- a/clickhouse_driver/connection.py
+++ b/clickhouse_driver/connection.py
@@ -553,6 +553,9 @@ def send_addendum(self):
             )
 
     def ping(self):
+        if not self.socket:
+            return None
+
         timeout = self.sync_request_timeout
 
         with self.timeout_setter(timeout):