diff --git a/Lib/test/test_types.py b/Lib/test/test_types.py
index d79429faf11..73fbdbf9b90 100644
--- a/Lib/test/test_types.py
+++ b/Lib/test/test_types.py
@@ -1051,6 +1051,8 @@ class SimpleNamespaceTests(unittest.TestCase):
 
         with self.assertRaises(TypeError):
             types.SimpleNamespace(1, 2, 3)
+        with self.assertRaises(TypeError):
+            types.SimpleNamespace(**{1: 2})
 
         self.assertEqual(len(ns1.__dict__), 0)
         self.assertEqual(vars(ns1), {})
diff --git a/Objects/namespaceobject.c b/Objects/namespaceobject.c
index 0bb30638445..d28c9133b4b 100644
--- a/Objects/namespaceobject.c
+++ b/Objects/namespaceobject.c
@@ -50,8 +50,12 @@ namespace_init(_PyNamespaceObject *ns, PyObject *args, PyObject *kwds)
             return -1;
         }
     }
-    if (kwds == NULL)
+    if (kwds == NULL) {
         return 0;
+    }
+    if (!PyArg_ValidateKeywordArguments(kwds)) {
+        return -1;
+    }
     return PyDict_Update(ns->ns_dict, kwds);
 }