diff --git a/litellm/llms/anthropic/chat/transformation.py b/litellm/llms/anthropic/chat/transformation.py
index 15fc482b34e..d55df5da16e 100644
--- a/litellm/llms/anthropic/chat/transformation.py
+++ b/litellm/llms/anthropic/chat/transformation.py
@@ -1962,8 +1962,13 @@ class AnthropicConfig(AnthropicModelInfo, BaseConfig):
                 optional_params.pop("metadata")
 
         # Remove internal LiteLLM parameters that should not be sent to Anthropic API
-        optional_params.pop("is_vertex_request", None)
-        optional_params.pop("client_metadata", None)
+        for internal_param in (
+            "is_vertex_request",
+            "client_metadata",
+            "vector_store_ids",
+            "vector_store_id",
+        ):
+            optional_params.pop(internal_param, None)
 
         # ``top_k`` is a provider-specific kwarg that bypasses
         # ``map_openai_params``; gate it here, the single boundary shared by
diff --git a/tests/test_litellm/llms/anthropic/chat/test_anthropic_chat_transformation.py b/tests/test_litellm/llms/anthropic/chat/test_anthropic_chat_transformation.py
index 25e2c3cda80..7138fc6f2e9 100644
--- a/tests/test_litellm/llms/anthropic/chat/test_anthropic_chat_transformation.py
+++ b/tests/test_litellm/llms/anthropic/chat/test_anthropic_chat_transformation.py
@@ -5996,6 +5996,25 @@ def test_client_metadata_stripped_from_anthropic_request():
     assert "client_metadata" not in result
 
 
+def test_transform_request_strips_vector_store_ids():
+    """vector_store_ids injected by proxy vector store hooks must not reach the Anthropic payload."""
+    config = AnthropicConfig()
+    result = config.transform_request(
+        model="claude-3-5-haiku-20241022",
+        messages=[{"role": "user", "content": "hello"}],
+        optional_params={
+            "max_tokens": 10,
+            "vector_store_ids": ["vs_abc123"],
+            "vector_store_id": "vs_abc123",
+        },
+        litellm_params={},
+        headers={},
+    )
+    assert "vector_store_ids" not in result
+    assert "vector_store_id" not in result
+    assert result["max_tokens"] == 10
+
+
 @pytest.mark.parametrize(
     "model",
     ["claude-fable-5", "claude-opus-4-7", "claude-opus-4-8-20260120"],