diff --git a/integration-tests/nghttpx_http2_test.go b/integration-tests/nghttpx_http2_test.go
index f31f1878..6db9bd5d 100644
--- a/integration-tests/nghttpx_http2_test.go
+++ b/integration-tests/nghttpx_http2_test.go
@@ -8,7 +8,6 @@ import (
 	"golang.org/x/net/http2"
 	"golang.org/x/net/http2/hpack"
 	"io"
-	"io/ioutil"
 	"net"
 	"net/http"
 	"regexp"
@@ -601,7 +600,7 @@ func TestH2H1ChunkedRequestBody(t *testing.T) {
 		if got := fmt.Sprint(r.TransferEncoding); got != want {
 			t.Errorf("Transfer-Encoding: %v; want %v", got, want)
 		}
-		body, err := ioutil.ReadAll(r.Body)
+		body, err := io.ReadAll(r.Body)
 		if err != nil {
 			t.Fatalf("Error reading r.body: %v", err)
 		}
diff --git a/integration-tests/server_tester.go b/integration-tests/server_tester.go
index 113e27d1..2522659e 100644
--- a/integration-tests/server_tester.go
+++ b/integration-tests/server_tester.go
@@ -12,7 +12,6 @@ import (
 	"golang.org/x/net/http2/hpack"
 	"golang.org/x/net/websocket"
 	"io"
-	"io/ioutil"
 	"net"
 	"net/http"
 	"net/http/httptest"
@@ -430,7 +429,7 @@ func (st *serverTester) http1(rp requestParam) (*serverResponse, error) {
 	if err != nil {
 		return nil, err
 	}
-	respBody, err := ioutil.ReadAll(resp.Body)
+	respBody, err := io.ReadAll(resp.Body)
 	if err != nil {
 		return nil, err
 	}
@@ -664,7 +663,7 @@ func cloneHeader(h http.Header) http.Header {
 }
 
 func noopHandler(w http.ResponseWriter, r *http.Request) {
-	ioutil.ReadAll(r.Body)
+	io.ReadAll(r.Body)
 }
 
 type APIResponse struct {