diff --git a/rclpy/rclpy/executors.py b/rclpy/rclpy/executors.py
index 8fff08931..223722726 100644
--- a/rclpy/rclpy/executors.py
+++ b/rclpy/rclpy/executors.py
@@ -262,7 +262,7 @@ async def _execute_client(self, client, seq_and_response):
         if sequence is not None:
             try:
                 future = client._pending_requests[sequence]
-            except IndexError:
+            except KeyError:
                 # The request was cancelled
                 pass
             else: