diff --git a/Lib/test/test_posix.py b/Lib/test/test_posix.py
index 35264f7..073e069 100644
--- a/Lib/test/test_posix.py
+++ b/Lib/test/test_posix.py
@@ -269,10 +269,11 @@
             # non-root cannot chown to root, raises OSError
             self.assertRaises(OSError, chown_func, first_param, 0, 0)
             check_stat(uid, gid)
-            self.assertRaises(OSError, chown_func, first_param, -1, 0)
-            check_stat(uid, gid)
             self.assertRaises(OSError, chown_func, first_param, 0, -1)
             check_stat(uid, gid)
+            if gid != 0:
+                self.assertRaises(OSError, chown_func, first_param, -1, 0)
+                check_stat(uid, gid)
         # test illegal types
         for t in str, float:
             self.assertRaises(TypeError, chown_func, first_param, t(uid), gid)