diff --git a/polkadot/runtime/parachains/src/hrmp/benchmarking.rs b/polkadot/runtime/parachains/src/hrmp/benchmarking.rs
index 86c63b3fc9060cb1da2622be92bfdb416baad4f8..26a7de6625359ed92d662edc0816b8848dfdb8b6 100644
--- a/polkadot/runtime/parachains/src/hrmp/benchmarking.rs
+++ b/polkadot/runtime/parachains/src/hrmp/benchmarking.rs
@@ -208,6 +208,9 @@ mod benchmarks {
 		assert_ok!(
 			Configuration::<T>::set_hrmp_max_parachain_inbound_channels(frame_system::RawOrigin::Root.into(), i + 1)
 		);
+		assert_ok!(
+			Configuration::<T>::set_max_downward_message_size(frame_system::RawOrigin::Root.into(), 1024)
+		);
 		// .. and enact it.
 		Configuration::<T>::initializer_on_new_session(&Shared::<T>::scheduled_session());