diff --git a/manifests/v1alpha3/katib-controller/rbac.yaml b/manifests/v1alpha3/katib-controller/rbac.yaml
index f2bf88a3ba2..ec56d617735 100644
--- a/manifests/v1alpha3/katib-controller/rbac.yaml
+++ b/manifests/v1alpha3/katib-controller/rbac.yaml
@@ -11,6 +11,7 @@ rules:
   - services
   - secrets
   - events
+  - namespaces
   verbs:
   - "*"
 - apiGroups:
diff --git a/pkg/webhook/v1alpha3/common/const.go b/pkg/webhook/v1alpha3/common/const.go
new file mode 100644
index 00000000000..2ec4b28efaa
--- /dev/null
+++ b/pkg/webhook/v1alpha3/common/const.go
@@ -0,0 +1,22 @@
+/*
+Copyright 2019 The Kubernetes 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 common
+
+const (
+	KatibMetricsCollectorInjection        = "katib-metricscollector-injection"
+	KatibMetricsCollectorInjectionEnabled = "enabled"
+)
diff --git a/pkg/webhook/v1alpha3/experiment/validation_webhook.go b/pkg/webhook/v1alpha3/experiment/validation_webhook.go
index 5af160c2fee..345dc3b5dbc 100644
--- a/pkg/webhook/v1alpha3/experiment/validation_webhook.go
+++ b/pkg/webhook/v1alpha3/experiment/validation_webhook.go
@@ -18,8 +18,11 @@ package experiment
 
 import (
 	"context"
+	"fmt"
 	"net/http"
 
+	v1 "k8s.io/api/core/v1"
+	ktypes "k8s.io/apimachinery/pkg/types"
 	"sigs.k8s.io/controller-runtime/pkg/client"
 	"sigs.k8s.io/controller-runtime/pkg/runtime/inject"
 	"sigs.k8s.io/controller-runtime/pkg/webhook/admission"
@@ -27,6 +30,7 @@ import (
 
 	experimentsv1alpha3 "github.com/kubeflow/katib/pkg/apis/controller/experiments/v1alpha3"
 	"github.com/kubeflow/katib/pkg/controller.v1alpha3/experiment/manifest"
+	"github.com/kubeflow/katib/pkg/webhook/v1alpha3/common"
 	"github.com/kubeflow/katib/pkg/webhook/v1alpha3/experiment/validator"
 )
 
@@ -51,6 +55,26 @@ func (v *experimentValidator) Handle(ctx context.Context, req types.Request) typ
 	if err != nil {
 		return admission.ErrorResponse(http.StatusBadRequest, err)
 	}
+
+	// After metrics collector sidecar injection in Job level done, delete validation for namespace labels
+	ns := &v1.Namespace{}
+	if err := v.client.Get(context.TODO(), ktypes.NamespacedName{Name: req.AdmissionRequest.Namespace}, ns); err != nil {
+		return admission.ErrorResponse(http.StatusInternalServerError, err)
+	}
+	validNS := true
+	if ns.Labels == nil {
+		validNS = false
+	} else {
+		if v, ok := ns.Labels[common.KatibMetricsCollectorInjection]; !ok || v != common.KatibMetricsCollectorInjectionEnabled {
+			validNS = false
+		}
+	}
+	if !validNS {
+		err = fmt.Errorf("Cannot create the Experiment %q in namespace %q: the namespace lacks label \"%s: %s\"",
+			inst.Name, req.AdmissionRequest.Namespace, common.KatibMetricsCollectorInjection, common.KatibMetricsCollectorInjectionEnabled)
+		return admission.ErrorResponse(http.StatusBadRequest, err)
+	}
+
 	err = v.ValidateExperiment(inst)
 	if err != nil {
 		return admission.ErrorResponse(http.StatusBadRequest, err)
diff --git a/pkg/webhook/v1alpha3/webhook.go b/pkg/webhook/v1alpha3/webhook.go
index 814261d1e14..fdd93cd877e 100644
--- a/pkg/webhook/v1alpha3/webhook.go
+++ b/pkg/webhook/v1alpha3/webhook.go
@@ -26,14 +26,13 @@ import (
 
 	experimentsv1alpha3 "github.com/kubeflow/katib/pkg/apis/controller/experiments/v1alpha3"
 	"github.com/kubeflow/katib/pkg/controller.v1alpha3/consts"
+	"github.com/kubeflow/katib/pkg/webhook/v1alpha3/common"
 	"github.com/kubeflow/katib/pkg/webhook/v1alpha3/experiment"
 	"github.com/kubeflow/katib/pkg/webhook/v1alpha3/pod"
 )
 
 const (
-	katibControllerName                   = "katib-controller"
-	katibMetricsCollectorInjection        = "katib-metricscollector-injection"
-	katibMetricsCollectorInjectionEnabled = "enabled"
+	katibControllerName = "katib-controller"
 )
 
 func AddToManager(m manager.Manager) error {
@@ -91,7 +90,7 @@ func register(manager manager.Manager, server *webhook.Server) error {
 	}
 	nsSelector := &metav1.LabelSelector{
 		MatchLabels: map[string]string{
-			katibMetricsCollectorInjection: katibMetricsCollectorInjectionEnabled,
+			common.KatibMetricsCollectorInjection: common.KatibMetricsCollectorInjectionEnabled,
 		},
 	}
 	injectWebhook, err := builder.NewWebhookBuilder().