diff --git a/Lib/zipfile.py b/Lib/zipfile.py
index dab595b..5f2efb9 100644
--- a/Lib/zipfile.py
+++ b/Lib/zipfile.py
@@ -978,7 +978,8 @@
             os.makedirs(upperdirs)
 
         if member.filename[-1] == '/':
-            os.mkdir(targetpath)
+            if not os.path.isdir(targetpath):
+                os.mkdir(targetpath)
             return targetpath
 
         source = self.open(member, pwd=pwd)