diff --git a/kwok/charts/crds/karpenter.sh_nodeclaims.yaml b/kwok/charts/crds/karpenter.sh_nodeclaims.yaml
index 24f0b8e538..83b294f119 100644
--- a/kwok/charts/crds/karpenter.sh_nodeclaims.yaml
+++ b/kwok/charts/crds/karpenter.sh_nodeclaims.yaml
@@ -361,6 +361,9 @@ spec:
                 - nodeClassRef
                 - requirements
               type: object
+              x-kubernetes-validations:
+                - message: spec is immutable
+                  rule: self == oldSelf
             status:
               description: NodeClaimStatus defines the observed state of NodeClaim
               properties:
diff --git a/pkg/apis/crds/karpenter.sh_nodeclaims.yaml b/pkg/apis/crds/karpenter.sh_nodeclaims.yaml
index 9683b31900..615402f1d6 100644
--- a/pkg/apis/crds/karpenter.sh_nodeclaims.yaml
+++ b/pkg/apis/crds/karpenter.sh_nodeclaims.yaml
@@ -359,6 +359,9 @@ spec:
                 - nodeClassRef
                 - requirements
               type: object
+              x-kubernetes-validations:
+                - message: spec is immutable
+                  rule: self == oldSelf
             status:
               description: NodeClaimStatus defines the observed state of NodeClaim
               properties:
diff --git a/pkg/apis/v1/nodeclaim.go b/pkg/apis/v1/nodeclaim.go
index 3b2789011e..d1d85f51c0 100644
--- a/pkg/apis/v1/nodeclaim.go
+++ b/pkg/apis/v1/nodeclaim.go
@@ -175,6 +175,7 @@ type NodeClaim struct {
 	metav1.TypeMeta   `json:",inline"`
 	metav1.ObjectMeta `json:"metadata,omitempty"`
 
+	// +kubebuilder:validation:XValidation:rule="self == oldSelf",message="spec is immutable"
 	// +required
 	Spec   NodeClaimSpec   `json:"spec"`
 	Status NodeClaimStatus `json:"status,omitempty"`