diff --git a/python/paddle/distributed/fleet/launch.py b/python/paddle/distributed/fleet/launch.py
index 4b629bc35ce59da9af0b72a2ab4ee44e587a86f1..17fa0a0c7c34744383d210a0fa409933d96dea21 100644
--- a/python/paddle/distributed/fleet/launch.py
+++ b/python/paddle/distributed/fleet/launch.py
@@ -156,7 +156,7 @@ def get_cluster_from_args(args, gpus):
     else:
         start_port = 6070
         if os.environ.get('FLAGS_START_PORT') is not None:
-            start_port = os.environ.get('FLAGS_START_PORT')
+            start_port = int(os.environ.get('FLAGS_START_PORT'))
 
         free_ports = [x for x in range(start_port, start_port + len(gpus))]