diff --git a/litellm/llms/vertex_httpx.py b/litellm/llms/vertex_httpx.py
index 94fbd0a13e..c784bf2e89 100644
--- a/litellm/llms/vertex_httpx.py
+++ b/litellm/llms/vertex_httpx.py
@@ -1586,6 +1586,8 @@ class VertexLLM(BaseLLM):
 
         if "instances" in optional_params:
             request_data["instances"] = optional_params["instances"]
+        elif isinstance(input, list):
+            request_data["instances"] = input
         else:
             # construct instances
             vertex_request_instance = Instance(**optional_params)
diff --git a/litellm/tests/test_amazing_vertex_completion.py b/litellm/tests/test_amazing_vertex_completion.py
index b7fc332417..75868a2f42 100644
--- a/litellm/tests/test_amazing_vertex_completion.py
+++ b/litellm/tests/test_amazing_vertex_completion.py
@@ -1836,7 +1836,7 @@ async def test_vertexai_multimodal_embedding():
         litellm.set_verbose = True
         response = await litellm.aembedding(
             model="vertex_ai/multimodalembedding@001",
-            instances=[
+            input=[
                 {
                     "image": {
                         "gcsUri": "gs://cloud-samples-data/vertex-ai/llm/prompts/landmark1.png"