diff --git a/python/semantic_kernel/connectors/redis.py b/python/semantic_kernel/connectors/redis.py
index 575624895aca..902337d1dacd 100644
--- a/python/semantic_kernel/connectors/redis.py
+++ b/python/semantic_kernel/connectors/redis.py
@@ -278,7 +278,7 @@ async def ensure_collection_exists(self, **kwargs) -> None:
             raise VectorStoreOperationException("Invalid index type supplied.")
         fields = _definition_to_redis_fields(self.definition, self.collection_type)
         index_definition = IndexDefinition(
-            prefix=f"{self.collection_name}:", index_type=INDEX_TYPE_MAP[self.collection_type]
+            prefix=[f"{self.collection_name}:"], index_type=INDEX_TYPE_MAP[self.collection_type]
         )
         await self.redis_database.ft(self.collection_name).create_index(fields, definition=index_definition, **kwargs)
 
diff --git a/python/tests/unit/connectors/memory/test_redis_store.py b/python/tests/unit/connectors/memory/test_redis_store.py
index e779ad945a97..2adb7e2aabdf 100644
--- a/python/tests/unit/connectors/memory/test_redis_store.py
+++ b/python/tests/unit/connectors/memory/test_redis_store.py
@@ -295,11 +295,22 @@ async def test_create_index(collection_hash, mock_ensure_collection_exists):
     await collection_hash.ensure_collection_exists()
 
 
+async def test_create_index_prefix_is_list(collection_hash, mock_ensure_collection_exists):
+    """Verify prefix is passed as a list, not a string (#13894)."""
+    await collection_hash.ensure_collection_exists()
+    mock_ensure_collection_exists.assert_called_once()
+    definition = mock_ensure_collection_exists.call_args.kwargs.get("definition")
+    assert definition is not None
+    prefix_idx = definition.args.index("PREFIX")
+    assert definition.args[prefix_idx + 1] == 1
+    assert definition.args[prefix_idx + 2] == f"{collection_hash.collection_name}:"
+
+
 async def test_create_index_manual(collection_hash, mock_ensure_collection_exists):
     from redis.commands.search.index_definition import IndexDefinition, IndexType
 
     fields = ["fields"]
-    index_definition = IndexDefinition(prefix="test:", index_type=IndexType.HASH)
+    index_definition = IndexDefinition(prefix=["test:"], index_type=IndexType.HASH)
     await collection_hash.ensure_collection_exists(index_definition=index_definition, fields=fields)