diff --git a/ppcls/engine/evaluation/retrieval.py b/ppcls/engine/evaluation/retrieval.py
index 54ef8e46f..b5f0c003e 100644
--- a/ppcls/engine/evaluation/retrieval.py
+++ b/ppcls/engine/evaluation/retrieval.py
@@ -15,7 +15,6 @@ from __future__ import absolute_import
 from __future__ import division
 from __future__ import print_function
 
-import platform
 from typing import Optional
 
 import numpy as np