diff --git a/Lib/test/test_posix.py b/Lib/test/test_posix.py
index 7478234..e0c84f2 100644
--- a/Lib/test/test_posix.py
+++ b/Lib/test/test_posix.py
@@ -580,6 +580,10 @@
     @test_support.requires_unicode
     def test_path_with_null_unicode(self):
         fn = test_support.TESTFN_UNICODE
+        try:
+            fn.encode(test_support.TESTFN_ENCODING)
+        except (UnicodeError, TypeError):
+            self.skipTest("Requires unicode filenames support")
         fn_with_NUL = fn + u'\0'
         self.addCleanup(test_support.unlink, fn)
         test_support.unlink(fn)