diff --git a/libcst/codemod/_cli.py b/libcst/codemod/_cli.py
index 91b85c4de..61e34e1c4 100644
--- a/libcst/codemod/_cli.py
+++ b/libcst/codemod/_cli.py
@@ -473,7 +473,7 @@ def _print_parallel_result(
             )
 
         # In unified diff mode, the code is a diff we must print.
-        if unified_diff:
+        if unified_diff and result.code:
             print(result.code)