diff --git a/Lib/posixpath.py b/Lib/posixpath.py
index 6eb45fd..0ec430d 100644
--- a/Lib/posixpath.py
+++ b/Lib/posixpath.py
@@ -262,7 +262,7 @@
         except KeyError:
             return path
         userhome = pwent.pw_dir
-    userhome = userhome.rstrip('/')
+    userhome = userhome.rstrip('/') or userhome
     return userhome + path[i:]
 
 
diff --git a/Lib/test/test_posixpath.py b/Lib/test/test_posixpath.py
index 46ac067..e6f750a 100644
--- a/Lib/test/test_posixpath.py
+++ b/Lib/test/test_posixpath.py
@@ -345,6 +345,11 @@
             self.assert_(isinstance(posixpath.expanduser("~root/"), basestring))
             self.assert_(isinstance(posixpath.expanduser("~foo/"), basestring))
 
+            orig_home = os.environ['HOME']
+            os.environ['HOME'] = '/'
+            self.assertEqual(posixpath.expanduser("~"), "/")
+            os.environ['HOME'] = orig_home
+
         self.assertRaises(TypeError, posixpath.expanduser)
 
     def test_expandvars(self):
diff --git a/Misc/NEWS b/Misc/NEWS
index bfcd9fa..fd35fad 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -212,6 +212,8 @@
 Library
 -------
 
+- Issue 5471: Fix os.path.expanduser() for $HOME set to '/'.
+
 - Issue 1326077: fix the formatting of SyntaxErrors by the traceback module.
 
 - Issue 1726172: fix IndexError in the case of and empty response in ftplib.