diff --git a/pkg/operator/ceph/object/cosi/controller.go b/pkg/operator/ceph/object/cosi/controller.go
index a11838bf7..b57c8ef0a 100644
--- a/pkg/operator/ceph/object/cosi/controller.go
+++ b/pkg/operator/ceph/object/cosi/controller.go
@@ -118,11 +118,17 @@ func (r *ReconcileCephCOSIDriver) Reconcile(context context.Context, request rec
 func (r *ReconcileCephCOSIDriver) reconcile(request reconcile.Request) (reconcile.Result, cephv1.CephCOSIDriver, error) {
 	cephCOSIDriver := &cephv1.CephCOSIDriver{}
 
-	// Fetch the CephCOSIDriver instance
-	err := r.client.Get(r.opManagerContext, request.NamespacedName, cephCOSIDriver)
-	logger.Debugf("CephCOSIDriver: %+v", cephCOSIDriver)
+	// Check No of instances of CephCOSIDriver
+	cephCOSIDriverList := &cephv1.CephCOSIDriverList{}
+	err := r.client.List(r.opManagerContext, cephCOSIDriverList)
 	if err != nil && client.IgnoreNotFound(err) != nil {
-		return reconcile.Result{}, *cephCOSIDriver, errors.Wrapf(err, "failed to get Ceph COSI Driver %s", request.NamespacedName)
+		return reconcile.Result{}, *cephCOSIDriver, errors.Wrap(err, "failed to list CephCOSIDriver")
+	}
+	if len(cephCOSIDriverList.Items) > 1 {
+		return reconcile.Result{}, *cephCOSIDriver, errors.New("more than one instance of CephCOSIDriver found")
+	} else if len(cephCOSIDriverList.Items) == 1 {
+		cephCOSIDriver = &cephCOSIDriverList.Items[0]
+		logger.Debugf("CephCOSIDriver: %+v", cephCOSIDriver)
 	}
 
 	// While in experimental mode, the COSI driver is not enabled by default
@@ -157,9 +163,9 @@ func (r *ReconcileCephCOSIDriver) reconcile(request reconcile.Request) (reconcil
 		cephCOSIDriver.Name = CephCOSIDriverName
 	}
 
-	// Set the default CephCOSIDriver namespace if not already set
-	if cephCOSIDriver.Namespace == "" {
-		cephCOSIDriver.Namespace = os.Getenv(k8sutil.PodNamespaceEnvVar)
+	// The ceph-cosi-driver CRD should be same namespace as the operator
+	if cephCOSIDriver.Namespace != os.Getenv(k8sutil.PodNamespaceEnvVar) {
+		return reconcile.Result{}, *cephCOSIDriver, errors.New("Ceph COSI Driver namespace must be same as operator")
 	}
 
 	// Check whether object store is running
diff --git a/pkg/operator/ceph/object/cosi/controller_test.go b/pkg/operator/ceph/object/cosi/controller_test.go
index ec6761e3c..6b4e9eba7 100644
--- a/pkg/operator/ceph/object/cosi/controller_test.go
+++ b/pkg/operator/ceph/object/cosi/controller_test.go
@@ -255,4 +255,60 @@ func TestCephCOSIDriverController(t *testing.T) {
 		assert.NoError(t, err)
 		assert.Equal(t, "quay.io/ceph/cosi:custom", cephCOSIDriverDeployment.Spec.Template.Spec.Containers[0].Image)
 	})
+
+	t.Run("ceph cosi driver CRD with custom namespace", func(t *testing.T) {
+		cephCOSIDriver := &cephv1.CephCOSIDriver{
+			ObjectMeta: metav1.ObjectMeta{
+				Name:      CephCOSIDriverName,
+				Namespace: "custom-namespace",
+			},
+			Spec: cephv1.CephCOSIDriverSpec{
+				Image:              "quay.io/ceph/cosi:custom",
+				DeploymentStrategy: cephv1.COSIDeploymentStrategyAuto,
+			},
+		}
+		r := setupNewEnvironment(cephCOSIDriver)
+		req := reconcile.Request{
+			NamespacedName: types.NamespacedName{
+				Name:      CephCOSIDriverName,
+				Namespace: "custom-namespace",
+			},
+		}
+		res, err := r.Reconcile(ctx, req)
+		assert.Error(t, err)
+		assert.Equal(t, false, res.Requeue)
+	})
+
+	t.Run("multiple ceph cosi driver CRDs", func(t *testing.T) {
+		cephCOSIDriver1 := &cephv1.CephCOSIDriver{
+			ObjectMeta: metav1.ObjectMeta{
+				Name:      "ceph-cosi-driver-1",
+				Namespace: namespace,
+			},
+			Spec: cephv1.CephCOSIDriverSpec{
+				Image:              "quay.io/ceph/cosi:custom",
+				DeploymentStrategy: cephv1.COSIDeploymentStrategyAuto,
+			},
+		}
+		cephCOSIDriver2 := &cephv1.CephCOSIDriver{
+			ObjectMeta: metav1.ObjectMeta{
+				Name:      "ceph-cosi-driver-2",
+				Namespace: namespace,
+			},
+			Spec: cephv1.CephCOSIDriverSpec{
+				Image:              "quay.io/ceph/cosi:custom",
+				DeploymentStrategy: cephv1.COSIDeploymentStrategyAuto,
+			},
+		}
+		r := setupNewEnvironment(cephCOSIDriver1, cephCOSIDriver2)
+		req := reconcile.Request{
+			NamespacedName: types.NamespacedName{
+				Name:      "ceph-cosi-driver-1",
+				Namespace: namespace,
+			},
+		}
+		res, err := r.Reconcile(ctx, req)
+		assert.Error(t, err)
+		assert.Equal(t, false, res.Requeue)
+	})
 }