diff --git a/internal/ingress/annotations/class/main.go b/internal/ingress/annotations/class/main.go
index 0f5284f43..b2fe32d63 100644
--- a/internal/ingress/annotations/class/main.go
+++ b/internal/ingress/annotations/class/main.go
@@ -41,30 +41,24 @@ var (
 // IsValid returns true if the given Ingress specify the ingress.class
 // annotation or IngressClassName resource for Kubernetes >= v1.18
 func IsValid(ing *networking.Ingress) bool {
-	// 1. with annotation
+	// 1. with annotation or IngressClass
 	ingress, ok := ing.GetAnnotations()[IngressKey]
-	if ok {
-		// empty annotation and same annotation on ingress
-		if ingress == "" && IngressClass == DefaultClass {
-			return true
-		}
-
-		return ingress == IngressClass
+	if !ok && ing.Spec.IngressClassName != nil {
+		ingress = *ing.Spec.IngressClassName
 	}
 
-	// 2. k8s < v1.18. Check default annotation
-	if !k8s.IsIngressV1Beta1Ready {
-		return IngressClass == DefaultClass
+	// empty ingress and IngressClass equal default
+	if len(ingress) == 0 && IngressClass == DefaultClass {
+		return true
 	}
 
-	// 3. without annotation and IngressClass. Check default annotation
-	if k8s.IngressClass == nil {
-		return IngressClass == DefaultClass
+	// k8s > v1.18.
+	// Processing may be redundant because k8s.IngressClass is obtained by IngressClass
+	// 3. without annotation and IngressClass. Check IngressClass
+	if k8s.IngressClass != nil {
+		return ingress == k8s.IngressClass.Name
 	}
 
 	// 4. with IngressClass
-	if ing.Spec.IngressClassName != nil {
-		return k8s.IngressClass.Name == *ing.Spec.IngressClassName
-	}
-	return false
+	return ingress == IngressClass
 }
diff --git a/internal/ingress/annotations/class/main_test.go b/internal/ingress/annotations/class/main_test.go
index 9aa891822..2d863f072 100644
--- a/internal/ingress/annotations/class/main_test.go
+++ b/internal/ingress/annotations/class/main_test.go
@@ -39,28 +39,32 @@ func TestIsValidClass(t *testing.T) {
 	}()
 
 	tests := []struct {
-		ingress    string
-		controller string
-		defClass   string
-		annotation bool
-		k8sClass   *networking.IngressClass
-		v1Ready    bool
-		isValid    bool
+		ingress          string
+		controller       string
+		defClass         string
+		annotation       bool
+		ingressClassName bool
+		k8sClass         *networking.IngressClass
+		v1Ready          bool
+		isValid          bool
 	}{
-		{"", "", "nginx", true, nil, false, true},
-		{"", "nginx", "nginx", true, nil, false, true},
-		{"nginx", "nginx", "nginx", true, nil, false, true},
-		{"custom", "custom", "nginx", true, nil, false, true},
-		{"", "killer", "nginx", true, nil, false, false},
-		{"custom", "nginx", "nginx", true, nil, false, false},
-		{"", "custom", "nginx", false,
+		{"", "", "nginx", true, false, nil, false, true},
+		{"", "nginx", "nginx", true, false, nil, false, true},
+		{"nginx", "nginx", "nginx", true, false, nil, false, true},
+		{"custom", "custom", "nginx", true, false, nil, false, true},
+		{"", "killer", "nginx", true, false, nil, false, false},
+		{"custom", "nginx", "nginx", true, false, nil, false, false},
+		{"nginx", "nginx", "nginx", false, true, nil, false, true},
+		{"custom", "nginx", "nginx", false, true, nil, true, false},
+		{"nginx", "nginx", "nginx", false, true, nil, true, true},
+		{"", "custom", "nginx", false, false,
 			&networking.IngressClass{
 				ObjectMeta: meta_v1.ObjectMeta{
 					Name: "custom",
 				},
 			},
 			false, false},
-		{"", "custom", "nginx", false,
+		{"", "custom", "nginx", false, false,
 			&networking.IngressClass{
 				ObjectMeta: meta_v1.ObjectMeta{
 					Name: "custom",
@@ -82,6 +86,9 @@ func TestIsValidClass(t *testing.T) {
 		if test.annotation {
 			ing.Annotations[IngressKey] = test.ingress
 		}
+		if test.ingressClassName {
+			ing.Spec.IngressClassName = &[]string{test.ingress}[0]
+		}
 
 		IngressClass = test.controller
 		DefaultClass = test.defClass