diff --git a/staging/src/k8s.io/apiextensions-apiserver/pkg/apiserver/customresource_handler_test.go b/staging/src/k8s.io/apiextensions-apiserver/pkg/apiserver/customresource_handler_test.go
index 46470bd2f87..c4431d0f544 100644
--- a/staging/src/k8s.io/apiextensions-apiserver/pkg/apiserver/customresource_handler_test.go
+++ b/staging/src/k8s.io/apiextensions-apiserver/pkg/apiserver/customresource_handler_test.go
@@ -22,7 +22,6 @@ import (
 	"encoding/json"
 	"errors"
 	"io"
-	"io/ioutil"
 	"net/http"
 	"net/http/httptest"
 	"os"
@@ -397,7 +396,7 @@ func TestRouting(t *testing.T) {
 						t.Errorf("expected delegated called %v, got %v", tc.ExpectDelegateCalled, delegateCalled)
 					}
 					result := recorder.Result()
-					content, _ := ioutil.ReadAll(result.Body)
+					content, _ := io.ReadAll(result.Body)
 					if e, a := expectStatus, result.StatusCode; e != a {
 						t.Log(string(content))
 						t.Errorf("expected %v, got %v", e, a)
@@ -1042,7 +1041,7 @@ func getOpenAPISpecFromFile() (*spec.Swagger, error) {
 	if err != nil {
 		return nil, err
 	}
-	byteSpec, err := ioutil.ReadFile(path)
+	byteSpec, err := os.ReadFile(path)
 	if err != nil {
 		return nil, err
 	}
diff --git a/staging/src/k8s.io/apiextensions-apiserver/pkg/cmd/server/testing/testserver.go b/staging/src/k8s.io/apiextensions-apiserver/pkg/cmd/server/testing/testserver.go
index e7ebf78beda..324d1be096d 100644
--- a/staging/src/k8s.io/apiextensions-apiserver/pkg/cmd/server/testing/testserver.go
+++ b/staging/src/k8s.io/apiextensions-apiserver/pkg/cmd/server/testing/testserver.go
@@ -19,7 +19,6 @@ package testing
 import (
 	"context"
 	"fmt"
-	"io/ioutil"
 	"net"
 	"os"
 	"path/filepath"
@@ -101,7 +100,7 @@ func StartTestServer(t Logger, _ *TestServerInstanceOptions, customFlags []strin
 		}
 	}()
 
-	result.TmpDir, err = ioutil.TempDir("", "apiextensions-apiserver")
+	result.TmpDir, err = os.MkdirTemp("", "apiextensions-apiserver")
 	if err != nil {
 		return result, fmt.Errorf("failed to create temp dir: %v", err)
 	}
diff --git a/staging/src/k8s.io/apiextensions-apiserver/test/integration/conversion/webhook.go b/staging/src/k8s.io/apiextensions-apiserver/test/integration/conversion/webhook.go
index b283b9a0cdb..71ecdc80cfb 100644
--- a/staging/src/k8s.io/apiextensions-apiserver/test/integration/conversion/webhook.go
+++ b/staging/src/k8s.io/apiextensions-apiserver/test/integration/conversion/webhook.go
@@ -21,7 +21,7 @@ import (
 	"crypto/x509"
 	"encoding/json"
 	"fmt"
-	"io/ioutil"
+	"io"
 	"net/http"
 	"net/http/httptest"
 	"strings"
@@ -84,7 +84,7 @@ type V1ReviewConverterFunc func(review *apiextensionsv1.ConversionReview) (*apie
 func NewReviewWebhookHandler(t *testing.T, v1beta1ConverterFunc V1Beta1ReviewConverterFunc, v1ConverterFunc V1ReviewConverterFunc) http.Handler {
 	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		defer r.Body.Close()
-		data, err := ioutil.ReadAll(r.Body)
+		data, err := io.ReadAll(r.Body)
 		if err != nil {
 			t.Error(err)
 			return
diff --git a/staging/src/k8s.io/apiextensions-apiserver/test/integration/fixtures/server.go b/staging/src/k8s.io/apiextensions-apiserver/test/integration/fixtures/server.go
index 72fba20d0c9..3772cab4235 100644
--- a/staging/src/k8s.io/apiextensions-apiserver/test/integration/fixtures/server.go
+++ b/staging/src/k8s.io/apiextensions-apiserver/test/integration/fixtures/server.go
@@ -17,7 +17,6 @@ limitations under the License.
 package fixtures
 
 import (
-	"io/ioutil"
 	"os"
 	"strings"
 	"time"
@@ -55,7 +54,7 @@ func StartDefaultServerWithConfigAccess(t servertesting.Logger, flags ...string)
 
 func startDefaultServer(t servertesting.Logger, flags ...string) (func(), servertesting.TestServer, error) {
 	// create kubeconfig which will not actually be used. But authz/authn needs it to startup.
-	fakeKubeConfig, err := ioutil.TempFile("", "kubeconfig")
+	fakeKubeConfig, err := os.CreateTemp("", "kubeconfig")
 	if err != nil {
 		return nil, servertesting.TestServer{}, err
 	}