diff --git a/swift3/controllers/multi_upload.py b/swift3/controllers/multi_upload.py
index 684cd3ea..1c355e6b 100644
--- a/swift3/controllers/multi_upload.py
+++ b/swift3/controllers/multi_upload.py
@@ -94,10 +94,12 @@ class PartController(Controller):
                                   'Unexpected query string parameter')
 
         try:
-            # TODO: check the range of partNumber
             part_number = int(req.params['partNumber'])
+            if part_number < 1 or DEFAULT_MAX_PARTS < part_number:
+                raise Exception()
         except Exception:
-            err_msg = 'Part number must be an integer'
+            err_msg = 'Part number must be an integer between 1 and %d,' \
+                      ' inclusive' % DEFAULT_MAX_PARTS
             raise InvalidArgument('partNumber', req.params['partNumber'],
                                   err_msg)
 
diff --git a/swift3/test/unit/test_multi_upload.py b/swift3/test/unit/test_multi_upload.py
index 32fd805a..a046ff8c 100644
--- a/swift3/test/unit/test_multi_upload.py
+++ b/swift3/test/unit/test_multi_upload.py
@@ -391,6 +391,27 @@ class TestSwift3MultiUpload(Swift3TestCase):
         status, headers, body = self.call_swift3(req)
         self.assertEquals(self._get_error_code(body), 'InvalidArgument')
 
+        req = Request.blank('/bucket/object?partNumber=invalid&uploadId=X',
+                            environ={'REQUEST_METHOD': 'PUT'},
+                            headers={'Authorization': 'AWS test:tester:hmac'},
+                            body='part object')
+        status, headers, body = self.call_swift3(req)
+        self.assertEquals(self._get_error_code(body), 'InvalidArgument')
+
+        req = Request.blank('/bucket/object?partNumber=0&uploadId=X',
+                            environ={'REQUEST_METHOD': 'PUT'},
+                            headers={'Authorization': 'AWS test:tester:hmac'},
+                            body='part object')
+        status, headers, body = self.call_swift3(req)
+        self.assertEquals(self._get_error_code(body), 'InvalidArgument')
+
+        req = Request.blank('/bucket/object?partNumber=1001&uploadId=X',
+                            environ={'REQUEST_METHOD': 'PUT'},
+                            headers={'Authorization': 'AWS test:tester:hmac'},
+                            body='part object')
+        status, headers, body = self.call_swift3(req)
+        self.assertEquals(self._get_error_code(body), 'InvalidArgument')
+
     @s3acl
     def test_object_upload_part(self):
         req = Request.blank('/bucket/object?partNumber=1&uploadId=X',