diff --git a/vllm/entrypoints/openai/protocol.py b/vllm/entrypoints/openai/protocol.py
index e380212a4d76b..bbd61a2c5dd59 100644
--- a/vllm/entrypoints/openai/protocol.py
+++ b/vllm/entrypoints/openai/protocol.py
@@ -82,6 +82,7 @@ class ModelCard(OpenAIBaseModel):
     owned_by: str = "vllm"
     root: Optional[str] = None
     parent: Optional[str] = None
+    max_model_len: Optional[int] = None
     permission: List[ModelPermission] = Field(default_factory=list)
 
 
diff --git a/vllm/entrypoints/openai/serving_engine.py b/vllm/entrypoints/openai/serving_engine.py
index 066acdf1c019a..ae659d19c878b 100644
--- a/vllm/entrypoints/openai/serving_engine.py
+++ b/vllm/entrypoints/openai/serving_engine.py
@@ -62,6 +62,7 @@ async def show_available_models(self) -> ModelList:
         """Show available models. Right now we only have one model."""
         model_cards = [
             ModelCard(id=served_model_name,
+                      max_model_len=self.max_model_len,
                       root=self.served_model_names[0],
                       permission=[ModelPermission()])
             for served_model_name in self.served_model_names