diff --git a/modules/openapi-generator/src/main/resources/dart2/serialization/native/native_class.mustache b/modules/openapi-generator/src/main/resources/dart2/serialization/native/native_class.mustache
index b4ba0b716a12..f48f75d3d215 100644
--- a/modules/openapi-generator/src/main/resources/dart2/serialization/native/native_class.mustache
+++ b/modules/openapi-generator/src/main/resources/dart2/serialization/native/native_class.mustache
@@ -163,7 +163,7 @@ class {{{classname}}} {
             : {{items.complexType}}.mapListFromJson(json[r'{{{baseName}}}']),
                 {{/items.complexType}}
                 {{^items.complexType}}
-            : mapCastOfType<String, List>(json, r'{{{baseName}}}'),
+            : (json[r'{{{baseName}}}'] as Map<String, dynamic>).map((k, v) => MapEntry(k, v == null ? {{#items.isNullable}}null{{/items.isNullable}}{{^items.isNullable}}const <{{items.items.dataType}}>[]{{/items.isNullable}} : (v as List).cast<{{items.items.dataType}}>())),
                 {{/items.complexType}}
               {{/items.isArray}}
               {{^items.isArray}}
diff --git a/modules/openapi-generator/src/test/resources/3_0/dart/petstore-with-fake-endpoints-models-for-testing.yaml b/modules/openapi-generator/src/test/resources/3_0/dart/petstore-with-fake-endpoints-models-for-testing.yaml
index a5700aa697f2..eec97cecc18f 100644
--- a/modules/openapi-generator/src/test/resources/3_0/dart/petstore-with-fake-endpoints-models-for-testing.yaml
+++ b/modules/openapi-generator/src/test/resources/3_0/dart/petstore-with-fake-endpoints-models-for-testing.yaml
@@ -1731,6 +1731,12 @@ components:
             type: object
             additionalProperties:
               type: string
+        map_of_array_integer:
+          type: object
+          additionalProperties:
+            type: array
+            items:
+              type: integer
     MixedPropertiesAndAdditionalPropertiesClass:
       type: object
       properties:
diff --git a/samples/openapi3/client/petstore/dart2/petstore_client_lib_fake/doc/AdditionalPropertiesClass.md b/samples/openapi3/client/petstore/dart2/petstore_client_lib_fake/doc/AdditionalPropertiesClass.md
index 859d4d0b7a0c..a563b58b9375 100644
--- a/samples/openapi3/client/petstore/dart2/petstore_client_lib_fake/doc/AdditionalPropertiesClass.md
+++ b/samples/openapi3/client/petstore/dart2/petstore_client_lib_fake/doc/AdditionalPropertiesClass.md
@@ -10,6 +10,7 @@ Name | Type | Description | Notes
 ------------ | ------------- | ------------- | -------------
 **mapProperty** | **Map<String, String>** |  | [optional] [default to const {}]
 **mapOfMapProperty** | [**Map<String, Map<String, String>>**](Map.md) |  | [optional] [default to const {}]
+**mapOfArrayInteger** | [**Map<String, List<int>>**](List.md) |  | [optional] [default to const {}]
 
 [[Back to Model list]](../README.md#documentation-for-models) [[Back to API list]](../README.md#documentation-for-api-endpoints) [[Back to README]](../README.md)
 
diff --git a/samples/openapi3/client/petstore/dart2/petstore_client_lib_fake/lib/model/additional_properties_class.dart b/samples/openapi3/client/petstore/dart2/petstore_client_lib_fake/lib/model/additional_properties_class.dart
index 1986d67dc9d9..4feb30a2c68a 100644
--- a/samples/openapi3/client/petstore/dart2/petstore_client_lib_fake/lib/model/additional_properties_class.dart
+++ b/samples/openapi3/client/petstore/dart2/petstore_client_lib_fake/lib/model/additional_properties_class.dart
@@ -15,30 +15,36 @@ class AdditionalPropertiesClass {
   AdditionalPropertiesClass({
     this.mapProperty = const {},
     this.mapOfMapProperty = const {},
+    this.mapOfArrayInteger = const {},
   });
 
   Map<String, String> mapProperty;
 
   Map<String, Map<String, String>> mapOfMapProperty;
 
+  Map<String, List<int>> mapOfArrayInteger;
+
   @override
   bool operator ==(Object other) => identical(this, other) || other is AdditionalPropertiesClass &&
     _deepEquality.equals(other.mapProperty, mapProperty) &&
-    _deepEquality.equals(other.mapOfMapProperty, mapOfMapProperty);
+    _deepEquality.equals(other.mapOfMapProperty, mapOfMapProperty) &&
+    _deepEquality.equals(other.mapOfArrayInteger, mapOfArrayInteger);
 
   @override
   int get hashCode =>
     // ignore: unnecessary_parenthesis
     (mapProperty.hashCode) +
-    (mapOfMapProperty.hashCode);
+    (mapOfMapProperty.hashCode) +
+    (mapOfArrayInteger.hashCode);
 
   @override
-  String toString() => 'AdditionalPropertiesClass[mapProperty=$mapProperty, mapOfMapProperty=$mapOfMapProperty]';
+  String toString() => 'AdditionalPropertiesClass[mapProperty=$mapProperty, mapOfMapProperty=$mapOfMapProperty, mapOfArrayInteger=$mapOfArrayInteger]';
 
   Map<String, dynamic> toJson() {
     final json = <String, dynamic>{};
       json[r'map_property'] = this.mapProperty;
       json[r'map_of_map_property'] = this.mapOfMapProperty;
+      json[r'map_of_array_integer'] = this.mapOfArrayInteger;
     return json;
   }
 
@@ -63,6 +69,9 @@ class AdditionalPropertiesClass {
       return AdditionalPropertiesClass(
         mapProperty: mapCastOfType<String, String>(json, r'map_property') ?? const {},
         mapOfMapProperty: mapCastOfType<String, dynamic>(json, r'map_of_map_property') ?? const {},
+        mapOfArrayInteger: json[r'map_of_array_integer'] == null
+          ? const {}
+            : (json[r'map_of_array_integer'] as Map<String, dynamic>).map((k, v) => MapEntry(k, v == null ? const <int>[] : (v as List).cast<int>())),
       );
     }
     return null;