diff --git a/mashumaro/meta/helpers.py b/mashumaro/meta/helpers.py
index 4bdb41d3..f9a09f4d 100644
--- a/mashumaro/meta/helpers.py
+++ b/mashumaro/meta/helpers.py
@@ -29,7 +29,7 @@ def type_name(t):
         return str(t)
     else:
         try:
-            return f"{t.__module__}.{t.__name__}"
+            return f"{t.__module__}.{t.__qualname__}"
         except AttributeError:
             return str(t)