diff --git a/python-scripts/setup.py b/python-scripts/setup.py
index 71d10b423366ec9e13a86312b3da4b07050dbed6..1a2c2db467408862efaa11653e833464f45da4d0 100644
--- a/python-scripts/setup.py
+++ b/python-scripts/setup.py
@@ -190,7 +190,7 @@ with open(result, "w") as f :
 constants = []
 const_files = os.listdir(const_dir)
 for const_file in const_files :
-    const_path = const_dir+const_file
+    const_path = const_dir+'/'+const_file
     if utils.isExt(const_path, "const_extension") :
         with open(const_path, "r") as f :
             constants.extend(utils.read_const(f))