diff --git a/scrapy/tests/test_utils_jsonrpc.py b/scrapy/tests/test_utils_jsonrpc.py
index f8f8b13fb..fe62fb319 100644
--- a/scrapy/tests/test_utils_jsonrpc.py
+++ b/scrapy/tests/test_utils_jsonrpc.py
@@ -36,6 +36,9 @@ class JsonRpcUtilsTestCase(unittest.TestCase):
         crawler = CrawlerMock([])
         self.json_decoder = ScrapyJSONDecoder(crawler=crawler)
 
+    def test_jsonrpc_client_call_args_kwargs_raises(self):
+        self.assertRaises(ValueError, jsonrpc_client_call, 'url', 'test', 'one', kw=123)
+
     def test_jsonrpc_client_call_request(self):
         ul = urllib_mock(1)
         jsonrpc_client_call('url', 'test', 'one', 2, _urllib=ul)
diff --git a/scrapy/utils/jsonrpc.py b/scrapy/utils/jsonrpc.py
index d9d4008c9..686a1d235 100644
--- a/scrapy/utils/jsonrpc.py
+++ b/scrapy/utils/jsonrpc.py
@@ -31,6 +31,8 @@ class JsonRpcError(Exception):
 def jsonrpc_client_call(url, method, *args, **kwargs):
     """Execute a JSON-RPC call on the given url"""
     _urllib = kwargs.pop('_urllib', urllib)
+    if args and kwargs:
+        raise ValueError("Pass *args or **kwargs but not both to jsonrpc_client_call")
     req = {'jsonrpc': '2.0', 'method': method, 'params': args or kwargs, 'id': 1}
     res = json.loads(_urllib.urlopen(url, json.dumps(req)).read())
     if 'result' in res: