diff --git a/packages/dynamite/lib/src/openapi_builder.dart b/packages/dynamite/lib/src/openapi_builder.dart
index 9763e6b0..0271d4ab 100644
--- a/packages/dynamite/lib/src/openapi_builder.dart
+++ b/packages/dynamite/lib/src/openapi_builder.dart
@@ -584,7 +584,7 @@ class OpenAPIBuilder implements Builder {
                                     b
                                       ..named = true
                                       ..name = _toDartName(parameter.name)
-                                      ..required = parameter.required ?? false;
+                                      ..required = (parameter.required ?? false) && defaultValueCode == null;
                                     if (parameter.schema != null) {
                                       b.type = refer(
                                         _makeNullable(