diff --git a/operator/pkg/tasks/deinit/cert_test.go b/operator/pkg/tasks/deinit/cert_test.go
new file mode 100644
index 000000000000..d8e0953fc589
--- /dev/null
+++ b/operator/pkg/tasks/deinit/cert_test.go
@@ -0,0 +1,191 @@
+/*
+Copyright 2024 The Karmada Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package tasks
+
+import (
+	"context"
+	"fmt"
+	"strings"
+	"testing"
+
+	corev1 "k8s.io/api/core/v1"
+	apierrors "k8s.io/apimachinery/pkg/api/errors"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	fakeclientset "k8s.io/client-go/kubernetes/fake"
+
+	"github.com/karmada-io/karmada/operator/pkg/constants"
+	"github.com/karmada-io/karmada/operator/pkg/util"
+	"github.com/karmada-io/karmada/operator/pkg/workflow"
+)
+
+func TestNewCleanupCertTask(t *testing.T) {
+	tests := []struct {
+		name     string
+		wantTask workflow.Task
+	}{
+		{
+			name: "NewCleanupCertTask_IsCalled_ExpectedWorkflowTask",
+			wantTask: workflow.Task{
+				Name:        "cleanup-cert",
+				Run:         runCleanupCert,
+				RunSubTasks: true,
+				Tasks: []workflow.Task{
+					newCleanupCertSubTask("karmada", util.KarmadaCertSecretName),
+					newCleanupCertSubTask("etcd", util.EtcdCertSecretName),
+					newCleanupCertSubTask("webhook", util.WebhookCertSecretName),
+				},
+			},
+		},
+	}
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			cleanupCertTask := NewCleanupCertTask()
+			if err := util.DeepEqualTasks(cleanupCertTask, test.wantTask); err != nil {
+				t.Errorf("unexpected error: %v", err)
+			}
+		})
+	}
+}
+
+func TestRunCleanupCert(t *testing.T) {
+	tests := []struct {
+		name    string
+		runData workflow.RunData
+		wantErr bool
+		errMsg  string
+	}{
+		{
+			name:    "RunCleanupCert_InvalidTypeAssertion_TypeAssertionIsInvalid",
+			runData: &MyTestData{Data: "test"},
+			wantErr: true,
+			errMsg:  "cleanup-cert task invoked with an invalid data struct",
+		},
+		{
+			name: "RunCleanupCert_ValidTypeAssertion_TypeAssertionIsValid",
+			runData: &TestDeInitData{
+				name:      "karmada-demo",
+				namespace: "test",
+			},
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			err := runCleanupCert(test.runData)
+			if err == nil && test.wantErr {
+				t.Errorf("expected error, but got none")
+			}
+			if err != nil && !test.wantErr {
+				t.Errorf("unexpected error: %v", err)
+			}
+			if err != nil && test.wantErr && !strings.Contains(err.Error(), test.errMsg) {
+				t.Errorf("expected %s error msg to contain %s", err.Error(), test.errMsg)
+			}
+		})
+	}
+}
+
+func TestRunCleanupCertSubTask(t *testing.T) {
+	tests := []struct {
+		name           string
+		owner          string
+		secretNameFunc util.Namefunc
+		runData        workflow.RunData
+		prep           func(workflow.RunData) error
+		verify         func(workflow.RunData) error
+		wantErr        bool
+		errMsg         string
+	}{
+		{
+			name:    "RunCleanupCertSubTask_InvalidTypeAssertion_TypeAssertionIsInvalid",
+			owner:   "karmada",
+			runData: &MyTestData{Data: "test"},
+			prep:    func(workflow.RunData) error { return nil },
+			verify:  func(workflow.RunData) error { return nil },
+			wantErr: true,
+			errMsg:  fmt.Sprintf("cleanup-%s-cert task invoked with an invalid data struct", "karmada"),
+		},
+		{
+			name:           "RunCleanupCertSubTask_WithKarmadaCertSecret_CertsHaveBeenCleanedUp",
+			owner:          "karmada",
+			secretNameFunc: util.KarmadaCertSecretName,
+			prep:           prepareKarmadaCertSecret,
+			verify:         verifyKarmadaCertSecretDeleted,
+			runData: &TestDeInitData{
+				name:         "karmada-demo",
+				namespace:    "test",
+				remoteClient: fakeclientset.NewSimpleClientset(),
+			},
+			wantErr: false,
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			if err := test.prep(test.runData); err != nil {
+				t.Errorf("failed to prep the run cleanup cert subtask: %v", err)
+			}
+			cleanupCertSubTask := runCleanupCertSubTask(test.owner, test.secretNameFunc)
+			err := cleanupCertSubTask(test.runData)
+			if err == nil && test.wantErr {
+				t.Errorf("expected error, but got none")
+			}
+			if err != nil && !test.wantErr {
+				t.Errorf("unexpected error: %v", err)
+			}
+			if err != nil && test.wantErr && !strings.Contains(err.Error(), test.errMsg) {
+				t.Errorf("expected %s error msg to contain %s", err.Error(), test.errMsg)
+			}
+			if err := test.verify(test.runData); err != nil {
+				t.Errorf("failed to verify run cleanup cert subtask: %v", err)
+			}
+		})
+	}
+}
+
+func prepareKarmadaCertSecret(rd workflow.RunData) error {
+	data := rd.(*TestDeInitData)
+	secretName := util.KarmadaCertSecretName(data.name)
+	_, err := data.remoteClient.CoreV1().Secrets(data.namespace).Create(context.TODO(), &corev1.Secret{
+		ObjectMeta: metav1.ObjectMeta{
+			Name:      secretName,
+			Namespace: data.namespace,
+			Labels:    constants.KarmadaOperatorLabel,
+		},
+		Type: corev1.SecretTypeOpaque,
+	}, metav1.CreateOptions{})
+	if err != nil {
+		return fmt.Errorf("failed to create secret: %v", err)
+	}
+	return nil
+}
+
+func verifyKarmadaCertSecretDeleted(rd workflow.RunData) error {
+	data := rd.(*TestDeInitData)
+	secretName := util.KarmadaCertSecretName(data.name)
+	secret, err := data.remoteClient.CoreV1().Secrets(data.namespace).Get(context.TODO(), secretName, metav1.GetOptions{})
+	if err == nil {
+		if val, exists := secret.Labels[constants.KarmadaOperatorLabelKeyName]; exists && val != "" {
+			return fmt.Errorf("expected secret %s to be deleted, but it still exists with label %s=%s", secretName, constants.KarmadaOperatorLabelKeyName, val)
+		}
+		return fmt.Errorf("expected secret %s to be deleted, but it still exists", secretName)
+	}
+	if apierrors.IsNotFound(err) {
+		return nil
+	}
+	return err
+}