diff --git a/aider/models.py b/aider/models.py
index 1c8e7754a..20bd94130 100644
--- a/aider/models.py
+++ b/aider/models.py
@@ -777,6 +777,17 @@ def sanity_check_model(io, model):
         check_pip_install_extra(
             io, "boto3", "AWS Bedrock models require the boto3 package.", ["boto3"]
         )
+    
+    # Check if this is a Vertex AI model and ensure google-cloud-aiplatform is installed
+    if model.name.startswith("vertex_ai/"):
+        from aider.utils import check_pip_install_extra
+
+        check_pip_install_extra(
+            io, 
+            "google.cloud.aiplatform", 
+            "Google Vertex AI models require the google-cloud-aiplatform package.", 
+            ["google-cloud-aiplatform"]
+        )
 
     if not model.info:
         show = True