diff --git a/Lib/test/test_winreg.py b/Lib/test/test_winreg.py
--- a/Lib/test/test_winreg.py
+++ b/Lib/test/test_winreg.py
@@ -335,6 +335,23 @@
         finally:
             DeleteKey(HKEY_CURRENT_USER, test_key_name)
 
+    def test_queryvalueex_return_value(self):
+        # Test for Issue #16759, return unsigned int from QueryValueEx.
+        # Reg2Py, which gets called by QueryValueEx, was returning a value
+        # generated by PyLong_FromLong. The implmentation now uses
+        # PyLong_FromUnsignedLong to match DWORD's size.
+        try:
+            with CreateKey(HKEY_CURRENT_USER, test_key_name) as ck:
+                self.assertNotEqual(ck.handle, 0)
+                test_val = 0x80000000
+                SetValueEx(ck, "test_name", None, REG_DWORD, test_val)
+                ret_val, ret_type = QueryValueEx(ck, "test_name")
+                self.assertEqual(ret_type, REG_DWORD)
+                self.assertEqual(ret_val, test_val)
+        finally:
+            DeleteKey(HKEY_CURRENT_USER, test_key_name)
+
+
 
 @unittest.skipUnless(REMOTE_NAME, "Skipping remote registry tests")
 class RemoteWinregTests(BaseWinregTests):
diff --git a/PC/winreg.c b/PC/winreg.c
--- a/PC/winreg.c
+++ b/PC/winreg.c
@@ -900,9 +900,9 @@
     switch (typ) {
         case REG_DWORD:
             if (retDataSize == 0)
-                obData = PyLong_FromLong(0);
+                obData = PyLong_FromUnsignedLong(0);
             else
-                obData = PyLong_FromLong(*(int *)retDataBuf);
+                obData = PyLong_FromUnsignedLong(*(int *)retDataBuf);
             break;
         case REG_SZ:
         case REG_EXPAND_SZ: