diff --git a/google/cloud/aiplatform_v1/services/prediction_service/async_client.py b/google/cloud/aiplatform_v1/services/prediction_service/async_client.py
index cca5013989..8f63f5c7ea 100644
--- a/google/cloud/aiplatform_v1/services/prediction_service/async_client.py
+++ b/google/cloud/aiplatform_v1/services/prediction_service/async_client.py
@@ -230,7 +230,7 @@ def __init__(
                 Callable[..., PredictionServiceTransport],
             ]
         ] = "grpc_asyncio",
-        client_options: Optional[ClientOptions] = None,
+        client_options: Optional[Union[ClientOptions, dict]] = None,
         client_info: gapic_v1.client_info.ClientInfo = DEFAULT_CLIENT_INFO,
     ) -> None:
         """Instantiates the prediction service async client.