diff --git a/lib/pipeline/generate/impl/model/model_content_builders.dart b/lib/pipeline/generate/impl/model/model_content_builders.dart
index 22c8796..354a434 100644
--- a/lib/pipeline/generate/impl/model/model_content_builders.dart
+++ b/lib/pipeline/generate/impl/model/model_content_builders.dart
@@ -127,6 +127,8 @@ String _generateAnnotatedModelCodeWithoutImports(
     buffer.writeln(StringHelper.generateComment(model.description));
   }
 
+  // Build @JsonSerializable annotation string for factory constructor
+  String? jsonSerializableAnnotation;
   final jsonConfig = SwaggerConfig.jsonSerializableConfig;
   if (jsonConfig != null) {
     final params = <String>[];
@@ -135,14 +137,19 @@ String _generateAnnotatedModelCodeWithoutImports(
     if (!jsonConfig.includeIfNull) params.add('includeIfNull: false');
 
     if (params.isNotEmpty) {
-      buffer.writeln('@JsonSerializable(${params.join(', ')})');
+      jsonSerializableAnnotation = '@JsonSerializable(${params.join(', ')})';
     }
   }
 
   buffer
     ..writeln('@freezed')
-    ..writeln('abstract class $className with _\$$className {')
-    ..writeln('  const factory $className({');
+    ..writeln('abstract class $className with _\$$className {');
+
+  // Add @JsonSerializable annotation on factory constructor if configured
+  if (jsonSerializableAnnotation != null) {
+    buffer.writeln('  $jsonSerializableAnnotation');
+  }
+  buffer.writeln('  const factory $className({');
 
   model.properties.forEach((propName, property) {
     final dartType = generator.getDartPropertyType(property);