diff --git a/pkg/controller/scheduling/scheduling_utils.go b/pkg/controller/scheduling/scheduling_utils.go
index 288b37f300b..d5ebb7c841f 100644
--- a/pkg/controller/scheduling/scheduling_utils.go
+++ b/pkg/controller/scheduling/scheduling_utils.go
@@ -46,7 +46,8 @@ func BuildSchedulingPolicy4Component(clusterName, compName string, affinity *app
 }
 
 func buildSchedulingPolicy(cluster *appsv1alpha1.Cluster, compSpec *appsv1alpha1.ClusterComponentSpec) (*appsv1alpha1.SchedulingPolicy, error) {
-	schedulingPolicy := cluster.Spec.SchedulingPolicy
+	// make a copy, or it will affect cluster's spec
+	schedulingPolicy := cluster.Spec.SchedulingPolicy.DeepCopy()
 	if compSpec != nil && compSpec.SchedulingPolicy != nil {
 		schedulingPolicy = compSpec.SchedulingPolicy
 	}