diff --git a/dargs/dargs.py b/dargs/dargs.py
index 6663c8b..02e4835 100644
--- a/dargs/dargs.py
+++ b/dargs/dargs.py
@@ -302,6 +302,9 @@ def _check_value(self, value: Any, path=None):
     def _check_strict(self, value: dict, path=None):
         allowed_keys = self.flatten_sub(value, path).keys()
         # curpath = [*path, self.name]
+        if not len(allowed_keys):
+            # no allowed keys defined, allow any keys
+            return
         for name in value.keys():
             if name not in allowed_keys:
                 raise ArgumentKeyError(path,
diff --git a/tests/test_checker.py b/tests/test_checker.py
index a294d52..bff457b 100644
--- a/tests/test_checker.py
+++ b/tests/test_checker.py
@@ -35,7 +35,7 @@ def test_name_type(self):
         # check any keywords
         ca = Argument("kwargs", dict)
         anydict = {"this": 1, "that": 2, "any": 3}
-        ca.check({"kwargs": anydict})
+        ca.check({"kwargs": anydict}, strict=True)
         ca.check_value(anydict)
 
     def test_sub_fields(self):