diff --git a/python/sglang/launch_server.py b/python/sglang/launch_server.py
index b2ad1b3209..6b0c25711c 100644
--- a/python/sglang/launch_server.py
+++ b/python/sglang/launch_server.py
@@ -1,5 +1,6 @@
 """Launch the inference server."""
 
+import os
 import sys
 
 from sglang.srt.server import launch_server