diff --git a/tests/test_litellm/proxy/management_endpoints/test_key_management_endpoints.py b/tests/test_litellm/proxy/management_endpoints/test_key_management_endpoints.py
index 50c96ce45ea..ed61ceac45c 100644
--- a/tests/test_litellm/proxy/management_endpoints/test_key_management_endpoints.py
+++ b/tests/test_litellm/proxy/management_endpoints/test_key_management_endpoints.py
@@ -18568,20 +18568,34 @@ async def test_rotate_master_key_rotates_sso_identity_assertions(
 
 
 @pytest.mark.asyncio
-async def test_rotate_master_key_reencrypts_vector_store_litellm_params():
-    """Master-key rotation re-encrypts the managed vector store credentials (step 4e)."""
+async def test_rotate_master_key_reencrypts_vector_store_litellm_params(monkeypatch):
+    """Master-key rotation re-encrypts the managed vector store credentials (step 4e) under the new key."""
+    import json
     from unittest.mock import AsyncMock, MagicMock
 
+    from litellm.proxy import proxy_server
     from litellm.proxy._types import LitellmUserRoles, UserAPIKeyAuth
+    from litellm.proxy.common_utils.encrypt_decrypt_utils import decrypt_if_encrypted_with
     from litellm.proxy.management_endpoints.key_management_endpoints import (
         _rotate_master_key,
     )
+    from litellm.proxy.vector_store_endpoints.litellm_params_encryption import encrypt_vector_store_litellm_params
+
+    monkeypatch.delenv("LITELLM_SALT_KEY", raising=False)
+    monkeypatch.setattr(proxy_server, "general_settings", {})
+    monkeypatch.setattr(proxy_server, "master_key", "sk-old-master-key")
+    stored = encrypt_vector_store_litellm_params({"api_key": "sk-vs-secret"})
 
     mock_prisma_client = AsyncMock()
     mock_prisma_client.db = MagicMock()
     mock_prisma_client.db.litellm_proxymodeltable.find_many = AsyncMock(return_value=[])
     mock_prisma_client.db.litellm_config.find_many = AsyncMock(return_value=[])
     mock_prisma_client.db.litellm_credentialstable.find_many = AsyncMock(return_value=[])
+    vector_stores = mock_prisma_client.db.litellm_managedvectorstorestable
+    vector_stores.find_many = AsyncMock(return_value=[{"vector_store_id": "vs_1", "litellm_params": stored}])
+    vector_stores.update_many = AsyncMock()
+    mock_prisma_client.tx = MagicMock()
+    mock_prisma_client.tx.return_value.__aenter__.return_value = mock_prisma_client.db
 
     with (
         patch("litellm.proxy.proxy_server.proxy_config", MagicMock()),
@@ -18589,10 +18603,6 @@ async def test_rotate_master_key_reencrypts_vector_store_litellm_params():
         patch("litellm.proxy.management_endpoints.key_management_endpoints.rotate_mcp_user_credentials_master_key"),
         patch("litellm.proxy.management_endpoints.key_management_endpoints.rotate_mcp_user_env_vars_master_key"),
         patch("litellm.proxy.management_endpoints.key_management_endpoints.rotate_sso_identity_assertions_master_key"),
-        patch(
-            "litellm.proxy.management_endpoints.key_management_endpoints.reencrypt_vector_store_litellm_params",
-            new_callable=AsyncMock,
-        ) as mock_reencrypt_vector_stores,
     ):
         await _rotate_master_key(
             prisma_client=mock_prisma_client,
@@ -18601,10 +18611,10 @@ async def test_rotate_master_key_reencrypts_vector_store_litellm_params():
             new_master_key="sk-new-master-key",
         )
 
-    mock_reencrypt_vector_stores.assert_awaited_once_with(
-        prisma_client=mock_prisma_client,
-        new_master_key="sk-new-master-key",
-    )
+    written = json.loads(vector_stores.update_many.await_args.kwargs["data"]["litellm_params"])
+    ciphertext = written["api_key"].removeprefix("litellm_enc::")
+    assert decrypt_if_encrypted_with(ciphertext, "sk-new-master-key") == "sk-vs-secret"
+    assert decrypt_if_encrypted_with(ciphertext, "sk-old-master-key") is None
 
 
 @pytest.mark.asyncio