diff --git a/datamodel_code_generator/types.py b/datamodel_code_generator/types.py
index 800938e7f..97a002455 100644
--- a/datamodel_code_generator/types.py
+++ b/datamodel_code_generator/types.py
@@ -16,6 +16,7 @@
     Tuple,
     Type,
     TypeVar,
+    Union,
 )
 
 from pydantic import create_model
@@ -71,7 +72,7 @@ class DataType(_BaseModel):
     is_dict: bool = False
     is_list: bool = False
     is_custom_type: bool = False
-    literals: List[str] = []
+    literals: List[Union[int, str]] = []
     use_standard_collections: bool = False
     use_generic_container: bool = False
     alias: Optional[str] = None