diff --git a/libs/vertexai/langchain_google_vertexai/_anthropic_utils.py b/libs/vertexai/langchain_google_vertexai/_anthropic_utils.py
index fd3721d2..bac60289 100644
--- a/libs/vertexai/langchain_google_vertexai/_anthropic_utils.py
+++ b/libs/vertexai/langchain_google_vertexai/_anthropic_utils.py
@@ -99,8 +99,8 @@ def _format_message_anthropic(message: Union[HumanMessage, AIMessage]):
 
                 if block["type"] == "image_url":
                     # convert format
-                    new_block["source"] = _format_image(block["image_url"]["url"])
-                    content.append(new_block)
+                    source = _format_image(block["image_url"]["url"])
+                    content.append({"type": "image", "source": source})
                     continue
 
                 if block["type"] == "tool_use":
diff --git a/libs/vertexai/tests/unit_tests/test_anthropic_utils.py b/libs/vertexai/tests/unit_tests/test_anthropic_utils.py
index 7f83bfb3..dafc193d 100644
--- a/libs/vertexai/tests/unit_tests/test_anthropic_utils.py
+++ b/libs/vertexai/tests/unit_tests/test_anthropic_utils.py
@@ -160,7 +160,7 @@
                     "role": "user",
                     "content": [
                         {
-                            "type": "image_url",
+                            "type": "image",
                             "source": {
                                 "type": "base64",
                                 "media_type": "image/png",