diff --git a/graphrag/query/indexer_adapters.py b/graphrag/query/indexer_adapters.py
index 0c6e54a8af..877d2bf780 100644
--- a/graphrag/query/indexer_adapters.py
+++ b/graphrag/query/indexer_adapters.py
@@ -228,9 +228,12 @@ def embed_community_reports(
         raise ValueError(error_msg)
 
     if embedding_col not in reports_df.columns:
-        reports_df[embedding_col] = reports_df.loc[:, source_col].apply(
-            lambda x: embedder.embed(x)
-        )
+        # Avoid using .apply with a lambda for improved performance.
+        # Use a list comprehension, which is faster for element-wise operations in pandas.
+        src = reports_df[source_col].to_list()
+        # No change in behavior, ensures a list of same length as DataFrame
+        embeddings = [embedder.embed(x) for x in src]
+        reports_df[embedding_col] = embeddings
 
     return reports_df