diff --git a/controller/sync_phase.go b/controller/sync_phase.go
index ee639f5273..2bb32aa548 100644
--- a/controller/sync_phase.go
+++ b/controller/sync_phase.go
@@ -11,13 +11,17 @@ func syncPhases(obj *unstructured.Unstructured) []v1alpha1.SyncPhase {
 	if hook.Skip(obj) {
 		return nil
 	} else if hook.IsHook(obj) {
-		var phases []v1alpha1.SyncPhase
+		phasesMap := make(map[v1alpha1.SyncPhase]bool)
 		for _, hookType := range hook.Types(obj) {
 			switch hookType {
 			case v1alpha1.HookTypePreSync, v1alpha1.HookTypeSync, v1alpha1.HookTypePostSync, v1alpha1.HookTypeSyncFail:
-				phases = append(phases, v1alpha1.SyncPhase(hookType))
+				phasesMap[v1alpha1.SyncPhase(hookType)] = true
 			}
 		}
+		var phases []v1alpha1.SyncPhase
+		for phase := range phasesMap {
+			phases = append(phases, phase)
+		}
 		return phases
 	} else {
 		return []v1alpha1.SyncPhase{v1alpha1.SyncPhaseSync}
diff --git a/controller/sync_phase_test.go b/controller/sync_phase_test.go
index 2fe35c41fa..1b0b9b7b4a 100644
--- a/controller/sync_phase_test.go
+++ b/controller/sync_phase_test.go
@@ -43,6 +43,15 @@ func TestSyncPhaseTwoPhases(t *testing.T) {
 	assert.ElementsMatch(t, []SyncPhase{SyncPhasePreSync, SyncPhasePostSync}, syncPhases(pod("PreSync,PostSync")))
 }
 
+func TestSyncDuplicatedPhases(t *testing.T) {
+	assert.ElementsMatch(t, []SyncPhase{SyncPhasePreSync}, syncPhases(pod("PreSync,PreSync")))
+	assert.ElementsMatch(t, []SyncPhase{SyncPhasePreSync}, syncPhases(podWithHelmHook("pre-install,pre-upgrade")))
+}
+
 func pod(hookType string) *unstructured.Unstructured {
 	return test.Annotate(test.NewPod(), "argocd.argoproj.io/hook", hookType)
 }
+
+func podWithHelmHook(hookType string) *unstructured.Unstructured {
+	return test.Annotate(test.NewPod(), "helm.sh/hook", hookType)
+}