diff --git a/metadata-ingestion/src/datahub/ingestion/source/mongodb.py b/metadata-ingestion/src/datahub/ingestion/source/mongodb.py
index 516f5b717e..cd78d1c030 100644
--- a/metadata-ingestion/src/datahub/ingestion/source/mongodb.py
+++ b/metadata-ingestion/src/datahub/ingestion/source/mongodb.py
@@ -394,6 +394,8 @@ class MongoDBSource(StatefulIngestionSourceBase):
                     customProperties={},
                 )
 
+                schema_metadata: Optional[SchemaMetadata] = None
+
                 if self.config.enableSchemaInference:
                     assert self.config.maxDocumentSize is not None
                     collection_schema = construct_schema_pymongo(