diff --git a/src/zeep/xsd/types/builtins.py b/src/zeep/xsd/types/builtins.py
index 8c5c6ba1..8f6f185f 100644
--- a/src/zeep/xsd/types/builtins.py
+++ b/src/zeep/xsd/types/builtins.py
@@ -136,7 +136,7 @@ def pythonvalue(self, value):
         if value.startswith("PT-"):
             value = value.replace("PT-", "PT")
             result = isodate.parse_duration(value)
-            return datetime.timedelta(0 - result.total_seconds())
+            return datetime.timedelta(seconds=0 - result.total_seconds())
         else:
             return isodate.parse_duration(value)
 
diff --git a/tests/test_xsd_builtins.py b/tests/test_xsd_builtins.py
index 4f055da9..41137e01 100644
--- a/tests/test_xsd_builtins.py
+++ b/tests/test_xsd_builtins.py
@@ -153,6 +153,11 @@ def test_pythonvalue(self):
         value = "\r  \nP0Y1347M0D\t "
         assert instance.pythonvalue(value) == expected
 
+    def test_pythonvalue_negative(self):
+        instance = builtins.Duration()
+        assert instance.pythonvalue("PT-30S") == datetime.timedelta(seconds=-30)
+        assert instance.pythonvalue("PT-1M") == datetime.timedelta(minutes=-1)
+
 
 class TestDateTime:
     def test_xmlvalue(self):