diff --git a/ariadne_codegen/client_generators/custom_arguments.py b/ariadne_codegen/client_generators/custom_arguments.py
index 0841a02..8dcb1de 100644
--- a/ariadne_codegen/client_generators/custom_arguments.py
+++ b/ariadne_codegen/client_generators/custom_arguments.py
@@ -5,6 +5,7 @@
     GraphQLEnumType,
     GraphQLInputObjectType,
     GraphQLInterfaceType,
+    GraphQLList,
     GraphQLNonNull,
     GraphQLObjectType,
     GraphQLScalarType,
@@ -23,6 +24,7 @@
     generate_dict,
     generate_import_from,
     generate_keyword,
+    generate_list_annotation,
     generate_name,
     generate_subscript,
     generate_tuple,
@@ -35,6 +37,8 @@
     BASE_MODEL_FILE_PATH,
     DICT,
     INPUT_SCALARS_MAP,
+    LIST,
+    TYPING_MODULE,
     UPLOAD_CLASS_NAME,
 )
 from .custom_generator_utils import get_final_type
@@ -77,12 +81,13 @@ def generate_arguments(
 
         for arg_name, arg_value in operation_args.items():
             final_type = get_final_type(arg_value)
+            is_list = isinstance(arg_value.type, GraphQLList)
             is_required = isinstance(arg_value.type, GraphQLNonNull)
             name = process_name(
                 arg_name, convert_to_snake_case=self.convert_to_snake_case
             )
             annotation, used_custom_scalar = self._parse_graphql_type_name(
-                final_type, not is_required
+                final_type, not is_required, is_list
             )
 
             self._accumulate_method_arguments(
@@ -93,8 +98,7 @@ def generate_arguments(
                 return_arguments_values,
                 arg_name,
                 name,
-                final_type,
-                is_required,
+                arg_value.type,
                 used_custom_scalar,
             )
 
@@ -125,12 +129,18 @@ def _accumulate_return_arguments(
         return_arguments_values: List[ast.expr],
         arg_name: str,
         name: str,
-        final_type: Union[GraphQLObjectType, GraphQLInterfaceType, GraphQLUnionType],
-        is_required: bool,
+        complete_type: Union[
+            GraphQLObjectType,
+            GraphQLInterfaceType,
+            GraphQLUnionType,
+            GraphQLNonNull,
+            GraphQLList,
+        ],
         used_custom_scalar: Optional[str],
     ) -> None:
         """Accumulates return arguments."""
-        constant_value = f"{final_type.name}!" if is_required else final_type.name
+        constant_value = self._generate_complete_type_name(complete_type)
+
         return_arg_dict_value = self._generate_return_arg_value(
             name, used_custom_scalar
         )
@@ -143,6 +153,28 @@ def _accumulate_return_arguments(
             )
         )
 
+    def _generate_complete_type_name(
+        self,
+        complete_type: Union[
+            GraphQLObjectType,
+            GraphQLInterfaceType,
+            GraphQLUnionType,
+            GraphQLNonNull,
+            GraphQLList,
+        ],
+    ) -> str:
+        if isinstance(complete_type, GraphQLNonNull):
+            if hasattr(complete_type, "of_type"):
+                return f"{self._generate_complete_type_name(complete_type.of_type)}!"
+            else:
+                return f"{self._generate_complete_type_name(complete_type.type)}"
+        if isinstance(complete_type, GraphQLList):
+            if hasattr(complete_type, "of_type"):
+                return f"[{self._generate_complete_type_name(complete_type.of_type)}]"
+            else:
+                return f"[{self._generate_complete_type_name(complete_type.type)}]"
+        return complete_type.name
+
     def _generate_return_arg_value(
         self, name: str, used_custom_scalar: Optional[str]
     ) -> Union[ast.Call, ast.Name]:
@@ -178,6 +210,7 @@ def _parse_graphql_type_name(
         self,
         type_: Union[GraphQLScalarType, GraphQLInputObjectType, GraphQLEnumType],
         nullable: bool = True,
+        is_list: bool = False,
     ) -> Tuple[Union[ast.Name, ast.Subscript], Optional[str]]:
         """Parses the GraphQL type name and determines if it is a custom scalar."""
         name = type_.name
@@ -205,7 +238,18 @@ def _parse_graphql_type_name(
                 self._used_custom_scalars.append(used_custom_scalar)
         else:
             raise ParsingError(f"Incorrect argument type {name}")
-        return generate_annotation_name(name, nullable), used_custom_scalar
+
+        if is_list:
+            self._add_import(generate_import_from(names=[LIST], from_=TYPING_MODULE))
+
+        return (
+            generate_annotation_name(name, nullable)
+            if not is_list
+            else generate_list_annotation(
+                generate_annotation_name(name, nullable=False), nullable
+            ),
+            used_custom_scalar,
+        )
 
     def add_custom_scalar_imports(self) -> None:
         """Adds imports for custom scalars used in the schema."""