diff --git a/cumulus/pallets/parachain-system/src/lib.rs b/cumulus/pallets/parachain-system/src/lib.rs
index 6857b08e66b7d..fa754ea29ccf5 100644
--- a/cumulus/pallets/parachain-system/src/lib.rs
+++ b/cumulus/pallets/parachain-system/src/lib.rs
@@ -45,7 +45,7 @@ use cumulus_primitives_core::{
 use cumulus_primitives_parachain_inherent::{MessageQueueChain, ParachainInherentData};
 use frame_support::{
 	defensive,
-	dispatch::{DispatchResult, Pays, PostDispatchInfo},
+	dispatch::DispatchResult,
 	ensure,
 	inherent::{InherentData, InherentIdentifier, ProvideInherent},
 	traits::{Get, HandleMessage},
@@ -567,11 +567,12 @@ pub mod pallet {
 		/// if the appropriate time has come.
 		#[pallet::call_index(0)]
 		#[pallet::weight((0, DispatchClass::Mandatory))]
-		// TODO: This weight should be corrected.
+		// TODO: This weight should be corrected. Currently the weight is registered manually in the
+		// call with `register_extra_weight_unchecked`.
 		pub fn set_validation_data(
 			origin: OriginFor<T>,
 			data: ParachainInherentData,
-		) -> DispatchResultWithPostInfo {
+		) -> DispatchResult {
 			ensure_none(origin)?;
 			assert!(
 				!<ValidationData<T>>::exists(),
@@ -692,7 +693,12 @@ pub mod pallet {
 				vfp.relay_parent_number,
 			));
 
-			Ok(PostDispatchInfo { actual_weight: Some(total_weight), pays_fee: Pays::No })
+			frame_system::Pallet::<T>::register_extra_weight_unchecked(
+				total_weight,
+				DispatchClass::Mandatory,
+			);
+
+			Ok(())
 		}
 
 		#[pallet::call_index(1)]
diff --git a/prdoc/pr_7327.prdoc b/prdoc/pr_7327.prdoc
new file mode 100644
index 0000000000000..bb2d7a671af31
--- /dev/null
+++ b/prdoc/pr_7327.prdoc
@@ -0,0 +1,11 @@
+title: Correctly register the weight n `set_validation_data` in `cumulus-pallet-parachain-system`
+
+doc:
+  - audience: Runtime Dev
+    description: |
+        The actual weight of the call was register as a refund, but the pre-dispatch weight is 0,
+        and we can't refund from 0. Now the actual weight is registered manually instead of ignored.
+
+crates:
+  - name: cumulus-pallet-parachain-system
+    bump: patch