diff --git a/staging/src/k8s.io/apiextensions-apiserver/pkg/apis/apiextensions/validation/validation.go b/staging/src/k8s.io/apiextensions-apiserver/pkg/apis/apiextensions/validation/validation.go
index 855bb249311..c5abb19f0bc 100644
--- a/staging/src/k8s.io/apiextensions-apiserver/pkg/apis/apiextensions/validation/validation.go
+++ b/staging/src/k8s.io/apiextensions-apiserver/pkg/apis/apiextensions/validation/validation.go
@@ -1605,7 +1605,7 @@ func validatePreserveUnknownFields(crd, oldCRD *apiextensions.CustomResourceDefi
 	var errs field.ErrorList
 	if crd != nil && crd.Spec.PreserveUnknownFields != nil && *crd.Spec.PreserveUnknownFields {
 		// disallow changing spec.preserveUnknownFields=false to spec.preserveUnknownFields=true
-		errs = append(errs, field.Invalid(field.NewPath("spec").Child("preserveUnknownFields"), crd.Spec.PreserveUnknownFields, "cannot set to true, set x-preserve-unknown-fields to true in spec.versions[*].schema instead"))
+		errs = append(errs, field.Invalid(field.NewPath("spec").Child("preserveUnknownFields"), crd.Spec.PreserveUnknownFields, "cannot set to true, set x-kubernetes-preserve-unknown-fields to true in spec.versions[*].schema instead"))
 	}
 	return errs
 }
diff --git a/staging/src/k8s.io/apiextensions-apiserver/pkg/apiserver/schema/cel/celcoststability_test.go b/staging/src/k8s.io/apiextensions-apiserver/pkg/apiserver/schema/cel/celcoststability_test.go
index b0c59b25f5b..e96d1891c7a 100644
--- a/staging/src/k8s.io/apiextensions-apiserver/pkg/apiserver/schema/cel/celcoststability_test.go
+++ b/staging/src/k8s.io/apiextensions-apiserver/pkg/apiserver/schema/cel/celcoststability_test.go
@@ -608,7 +608,7 @@ func TestCelCostStability(t *testing.T) {
 			}),
 			expectCost: map[string]int64{
 				// 'kind', 'apiVersion', 'metadata.name' and 'metadata.generateName' are always accessible
-				// even if not specified in the schema, regardless of if x-preserve-unknown-fields is set.
+				// even if not specified in the schema, regardless of if x-kubernetes-preserve-unknown-fields is set.
 				"self.embedded.kind == 'Pod'":                          4,
 				"self.embedded.apiVersion == 'v1'":                     4,
 				"self.embedded.metadata.name == 'foo'":                 5,
diff --git a/staging/src/k8s.io/apiextensions-apiserver/pkg/apiserver/schema/cel/validation_test.go b/staging/src/k8s.io/apiextensions-apiserver/pkg/apiserver/schema/cel/validation_test.go
index 09810a947de..8e0b26a1cdc 100644
--- a/staging/src/k8s.io/apiextensions-apiserver/pkg/apiserver/schema/cel/validation_test.go
+++ b/staging/src/k8s.io/apiextensions-apiserver/pkg/apiserver/schema/cel/validation_test.go
@@ -775,7 +775,7 @@ func TestValidationExpressions(t *testing.T) {
 			}),
 			valid: []string{
 				// 'kind', 'apiVersion', 'metadata.name' and 'metadata.generateName' are always accessible
-				// even if not specified in the schema, regardless of if x-preserve-unknown-fields is set.
+				// even if not specified in the schema, regardless of if x-kubernetes-preserve-unknown-fields is set.
 				"self.embedded.kind == 'Pod'",
 				"self.embedded.apiVersion == 'v1'",
 				"self.embedded.metadata.name == 'foo'",
@@ -785,7 +785,7 @@ func TestValidationExpressions(t *testing.T) {
 				"has(self.embedded)",
 			},
 			// only field declared in the schema can be field selected in CEL expressions, regardless of if
-			// x-preserve-unknown-fields is set.
+			// x-kubernetes-preserve-unknown-fields is set.
 			errors: map[string]string{
 				"has(self.embedded.spec)": "undefined field 'spec'",
 			},
diff --git a/staging/src/k8s.io/apiextensions-apiserver/pkg/apiserver/schema/cel/values.go b/staging/src/k8s.io/apiextensions-apiserver/pkg/apiserver/schema/cel/values.go
index 4fa90ab106f..f012ffdc45a 100644
--- a/staging/src/k8s.io/apiextensions-apiserver/pkg/apiserver/schema/cel/values.go
+++ b/staging/src/k8s.io/apiextensions-apiserver/pkg/apiserver/schema/cel/values.go
@@ -84,7 +84,7 @@ func UnstructuredToVal(unstructured interface{}, schema *structuralschema.Struct
 				},
 			}
 		}
-		// A object with x-preserve-unknown-fields but no properties or additionalProperties is treated
+		// A object with x-kubernetes-preserve-unknown-fields but no properties or additionalProperties is treated
 		// as an empty object.
 		if schema.XPreserveUnknownFields {
 			return &unstructuredMap{
diff --git a/test/conformance/testdata/conformance.yaml b/test/conformance/testdata/conformance.yaml
index 6981884b373..53d6f30a7ea 100755
--- a/test/conformance/testdata/conformance.yaml
+++ b/test/conformance/testdata/conformance.yaml
@@ -246,20 +246,21 @@
     update to reflect the rename.
   release: v1.16
   file: test/e2e/apimachinery/crd_publish_openapi.go
-- testname: Custom Resource OpenAPI Publish, with x-preserve-unknown-fields at root
+- testname: Custom Resource OpenAPI Publish, with x-kubernetes-preserve-unknown-fields
+    at root
   codename: '[sig-api-machinery] CustomResourcePublishOpenAPI [Privileged:ClusterAdmin]
     works for CRD preserving unknown fields at the schema root [Conformance]'
-  description: Register a custom resource definition with x-preserve-unknown-fields
+  description: Register a custom resource definition with x-kubernetes-preserve-unknown-fields
     in the schema root. Attempt to create and apply a change a custom resource, via
     kubectl; kubectl validation MUST accept unknown properties. Attempt kubectl explain;
     the output MUST show the custom resource KIND.
   release: v1.16
   file: test/e2e/apimachinery/crd_publish_openapi.go
-- testname: Custom Resource OpenAPI Publish, with x-preserve-unknown-fields in embedded
-    object
+- testname: Custom Resource OpenAPI Publish, with x-kubernetes-preserve-unknown-fields
+    in embedded object
   codename: '[sig-api-machinery] CustomResourcePublishOpenAPI [Privileged:ClusterAdmin]
     works for CRD preserving unknown fields in an embedded object [Conformance]'
-  description: Register a custom resource definition with x-preserve-unknown-fields
+  description: Register a custom resource definition with x-kubernetes-preserve-unknown-fields
     in an embedded object. Attempt to create and apply a change a custom resource,
     via kubectl; kubectl validation MUST accept unknown properties. Attempt kubectl
     explain; the output MUST show that x-preserve-unknown-properties is used on the
@@ -279,10 +280,11 @@
     validation should be the same.
   release: v1.16
   file: test/e2e/apimachinery/crd_publish_openapi.go
-- testname: Custom Resource OpenAPI Publish, with x-preserve-unknown-fields in object
+- testname: Custom Resource OpenAPI Publish, with x-kubernetes-preserve-unknown-fields
+    in object
   codename: '[sig-api-machinery] CustomResourcePublishOpenAPI [Privileged:ClusterAdmin]
     works for CRD without validation schema [Conformance]'
-  description: Register a custom resource definition with x-preserve-unknown-fields
+  description: Register a custom resource definition with x-kubernetes-preserve-unknown-fields
     in the top level object. Attempt to create and apply a change a custom resource,
     via kubectl; kubectl validation MUST accept unknown properties. Attempt kubectl
     explain; the output MUST contain a valid DESCRIPTION stanza.
diff --git a/test/e2e/apimachinery/crd_publish_openapi.go b/test/e2e/apimachinery/crd_publish_openapi.go
index 58a10effbc0..f8ca3d64a32 100644
--- a/test/e2e/apimachinery/crd_publish_openapi.go
+++ b/test/e2e/apimachinery/crd_publish_openapi.go
@@ -144,8 +144,8 @@ var _ = SIGDescribe("CustomResourcePublishOpenAPI [Privileged:ClusterAdmin]", fu
 
 	/*
 		Release: v1.16
-		Testname: Custom Resource OpenAPI Publish, with x-preserve-unknown-fields in object
-		Description: Register a custom resource definition with x-preserve-unknown-fields in the top level object.
+		Testname: Custom Resource OpenAPI Publish, with x-kubernetes-preserve-unknown-fields in object
+		Description: Register a custom resource definition with x-kubernetes-preserve-unknown-fields in the top level object.
 		Attempt to create and apply a change a custom resource, via kubectl; kubectl validation MUST accept unknown
 		properties. Attempt kubectl explain; the output MUST contain a valid DESCRIPTION stanza.
 	*/
@@ -185,8 +185,8 @@ var _ = SIGDescribe("CustomResourcePublishOpenAPI [Privileged:ClusterAdmin]", fu
 
 	/*
 		Release: v1.16
-		Testname: Custom Resource OpenAPI Publish, with x-preserve-unknown-fields at root
-		Description: Register a custom resource definition with x-preserve-unknown-fields in the schema root.
+		Testname: Custom Resource OpenAPI Publish, with x-kubernetes-preserve-unknown-fields at root
+		Description: Register a custom resource definition with x-kubernetes-preserve-unknown-fields in the schema root.
 		Attempt to create and apply a change a custom resource, via kubectl; kubectl validation MUST accept unknown
 		properties. Attempt kubectl explain; the output MUST show the custom resource KIND.
 	*/
@@ -226,8 +226,8 @@ var _ = SIGDescribe("CustomResourcePublishOpenAPI [Privileged:ClusterAdmin]", fu
 
 	/*
 		Release: v1.16
-		Testname: Custom Resource OpenAPI Publish, with x-preserve-unknown-fields in embedded object
-		Description: Register a custom resource definition with x-preserve-unknown-fields in an embedded object.
+		Testname: Custom Resource OpenAPI Publish, with x-kubernetes-preserve-unknown-fields in embedded object
+		Description: Register a custom resource definition with x-kubernetes-preserve-unknown-fields in an embedded object.
 		Attempt to create and apply a change a custom resource, via kubectl; kubectl validation MUST accept unknown
 		properties. Attempt kubectl explain; the output MUST show that x-preserve-unknown-properties is used on the
 		nested field.