diff --git a/python/ray/data/datasource/datasink.py b/python/ray/data/datasource/datasink.py
index 0832e0539fd16..fe4d4cf4ef9a3 100644
--- a/python/ray/data/datasource/datasink.py
+++ b/python/ray/data/datasource/datasink.py
@@ -98,7 +98,7 @@ def on_write_complete(self, write_result_blocks: List[Block]) -> WriteResult:
         aggregated_results_str = ""
         for k in fields(aggregated_write_results.__class__):
             v = getattr(aggregated_write_results, k.name)
-            aggregated_results_str += f"\t{k}: {v}\n"
+            aggregated_results_str += f"\t- {k.name}: {v}\n"
 
         logger.info(
             f"Write operation succeeded. Aggregated write results:\n"