diff --git a/inference_schema/schema_decorators.py b/inference_schema/schema_decorators.py
index 719097d..63e7668 100644
--- a/inference_schema/schema_decorators.py
+++ b/inference_schema/schema_decorators.py
@@ -54,7 +54,7 @@ def decorator_input(user_run, instance, args, kwargs):
                                     'is not in the decorated function.'.format(param_name))
                 param_position = arg_names.index(param_name)
                 args[param_position] = _deserialize_input_argument(args[param_position], param_type, param_name)
-            elif param_name not in kwargs.keys() and optional:
+            elif optional and (param_name not in kwargs.keys() or not kwargs[param_name]):
                 pass
             else:
                 kwargs[param_name] = _deserialize_input_argument(kwargs[param_name], param_type, param_name)
diff --git a/tests/test_pandas_parameter_type.py b/tests/test_pandas_parameter_type.py
index 971c4a1..28a4f94 100644
--- a/tests/test_pandas_parameter_type.py
+++ b/tests/test_pandas_parameter_type.py
@@ -110,6 +110,21 @@ def test_pandas_params_handling_without_params(self, decorated_pandas_func_param
         assert result[0][0] == "this is a string starting with"
         assert result[1] == 0
 
+    def test_pandas_params_handling_with_none_params(self, decorated_pandas_func_parameters):
+        pandas_input_data = {
+            "columns": [
+                "sentence1"
+            ],
+            "data": [
+                ["this is a string starting with"]
+            ],
+            "index": [0]
+        }
+        parameters = None
+        result = decorated_pandas_func_parameters(pandas_input_data, params=parameters)
+        assert result[0][0] == "this is a string starting with"
+        assert result[1] == 0
+
 
 class TestNestedType(object):