diff --git a/audio/export_test.go b/audio/export_test.go
index 0453b6b1a..e55312c03 100644
--- a/audio/export_test.go
+++ b/audio/export_test.go
@@ -16,7 +16,6 @@ package audio
 
 import (
 	"io"
-	"io/ioutil"
 	"sync"
 )
 
@@ -64,7 +63,7 @@ func (p *dummyPlayer) Play() {
 	p.playing = true
 	p.m.Unlock()
 	go func() {
-		if _, err := ioutil.ReadAll(p.r); err != nil {
+		if _, err := io.ReadAll(p.r); err != nil {
 			panic(err)
 		}
 		p.m.Lock()
diff --git a/audio/internal/convert/resampling_test.go b/audio/internal/convert/resampling_test.go
index a971180c3..590931a4a 100644
--- a/audio/internal/convert/resampling_test.go
+++ b/audio/internal/convert/resampling_test.go
@@ -16,7 +16,7 @@ package convert_test
 
 import (
 	"bytes"
-	"io/ioutil"
+	"io"
 	"math"
 	"testing"
 
@@ -70,7 +70,7 @@ func TestResampling(t *testing.T) {
 	for _, c := range cases {
 		inB := newSoundBytes(c.In)
 		outS := convert.NewResampling(bytes.NewReader(inB), int64(len(inB)), c.In, c.Out)
-		gotB, err := ioutil.ReadAll(outS)
+		gotB, err := io.ReadAll(outS)
 		if err != nil {
 			t.Fatal(err)
 		}
diff --git a/cmd/ebitenmobile/gobind.go b/cmd/ebitenmobile/gobind.go
index ca1afede3..1149bfd9d 100644
--- a/cmd/ebitenmobile/gobind.go
+++ b/cmd/ebitenmobile/gobind.go
@@ -21,7 +21,6 @@ package main
 import (
 	"flag"
 	"fmt"
-	"io/ioutil"
 	"log"
 	"os"
 	"os/exec"
@@ -82,7 +81,7 @@ func invokeOriginalGobind(lang string) (pkgName string, err error) {
 
 func run() error {
 	writeFile := func(filename string, content string) error {
-		if err := ioutil.WriteFile(filepath.Join(*outdir, filename), []byte(content), 0644); err != nil {
+		if err := os.WriteFile(filepath.Join(*outdir, filename), []byte(content), 0644); err != nil {
 			return err
 		}
 		return nil
diff --git a/cmd/ebitenmobile/gomobile.go b/cmd/ebitenmobile/gomobile.go
index ce4106de6..ab14c2e09 100644
--- a/cmd/ebitenmobile/gomobile.go
+++ b/cmd/ebitenmobile/gomobile.go
@@ -17,7 +17,6 @@ package main
 import (
 	_ "embed"
 	"fmt"
-	"io/ioutil"
 	"os"
 	"os/exec"
 	"path/filepath"
@@ -79,7 +78,7 @@ func exe(filename string) string {
 }
 
 func prepareGomobileCommands() (string, error) {
-	tmp, err := ioutil.TempDir("", "ebitenmobile-")
+	tmp, err := os.MkdirTemp("", "ebitenmobile-")
 	if err != nil {
 		return "", err
 	}
@@ -121,7 +120,7 @@ func prepareGomobileCommands() (string, error) {
 	if err := runGo("mod", "init", modname); err != nil {
 		return tmp, err
 	}
-	if err := ioutil.WriteFile("tools.go", []byte(fmt.Sprintf(`%s
+	if err := os.WriteFile("tools.go", []byte(fmt.Sprintf(`%s
 
 package %s
 
@@ -160,7 +159,7 @@ import (
 	if err := os.Mkdir("src", 0755); err != nil {
 		return tmp, err
 	}
-	if err := ioutil.WriteFile(filepath.Join("src", "gobind.go"), gobind_go, 0644); err != nil {
+	if err := os.WriteFile(filepath.Join("src", "gobind.go"), gobind_go, 0644); err != nil {
 		return tmp, err
 	}
 
diff --git a/cmd/ebitenmobile/main.go b/cmd/ebitenmobile/main.go
index 2fbf25370..25b44bb56 100644
--- a/cmd/ebitenmobile/main.go
+++ b/cmd/ebitenmobile/main.go
@@ -23,7 +23,6 @@ package main
 import (
 	"flag"
 	"fmt"
-	"io/ioutil"
 	"log"
 	"os"
 	"os/exec"
@@ -246,13 +245,13 @@ func doBind(args []string, flagset *flag.FlagSet, buildOS string) error {
 			frameworkNameBase = strings.Title(frameworkNameBase)
 			dir := filepath.Join(buildO, name, frameworkNameBase+".framework", "Versions", "A")
 
-			if err := ioutil.WriteFile(filepath.Join(dir, "Headers", prefixUpper+"EbitenViewController.h"), []byte(replacePrefixes(objcH)), 0644); err != nil {
+			if err := os.WriteFile(filepath.Join(dir, "Headers", prefixUpper+"EbitenViewController.h"), []byte(replacePrefixes(objcH)), 0644); err != nil {
 				return err
 			}
 			// TODO: Remove 'Ebitenmobileview.objc.h' here. Now it is hard since there is a header file importing
 			// that header file.
 
-			fs, err := ioutil.ReadDir(filepath.Join(dir, "Headers"))
+			fs, err := os.ReadDir(filepath.Join(dir, "Headers"))
 			if err != nil {
 				return err
 			}
diff --git a/ebitenutil/file_js.go b/ebitenutil/file_js.go
index 3df1d3e75..9c6be7eb4 100644
--- a/ebitenutil/file_js.go
+++ b/ebitenutil/file_js.go
@@ -16,7 +16,7 @@ package ebitenutil
 
 import (
 	"bytes"
-	"io/ioutil"
+	"io"
 	"net/http"
 )
 
@@ -40,7 +40,7 @@ func OpenFile(path string) (ReadSeekCloser, error) {
 	if err != nil {
 		return nil, err
 	}
-	body, err := ioutil.ReadAll(res.Body)
+	body, err := io.ReadAll(res.Body)
 	if err != nil {
 		return nil, err
 	}
diff --git a/examples/audio/main.go b/examples/audio/main.go
index 53d4fc193..6f62d4fa4 100644
--- a/examples/audio/main.go
+++ b/examples/audio/main.go
@@ -27,7 +27,6 @@ import (
 	"image/color"
 	_ "image/png"
 	"io"
-	"io/ioutil"
 	"log"
 	"time"
 
@@ -179,7 +178,7 @@ func NewPlayer(game *Game, audioContext *audio.Context, musicType musicType) (*P
 			log.Fatal(err)
 			return
 		}
-		b, err := ioutil.ReadAll(s)
+		b, err := io.ReadAll(s)
 		if err != nil {
 			log.Fatal(err)
 			return
diff --git a/examples/keyboard/keyboard/gen.go b/examples/keyboard/keyboard/gen.go
index a4639cc2a..8678d1b5c 100644
--- a/examples/keyboard/keyboard/gen.go
+++ b/examples/keyboard/keyboard/gen.go
@@ -19,11 +19,9 @@ package main
 
 import (
 	"bytes"
-	"errors"
 	"image"
 	"image/color"
 	"image/png"
-	"io/ioutil"
 	"log"
 	"os"
 	"os/exec"
@@ -46,13 +44,7 @@ var (
 )
 
 func init() {
-	f, err := os.Open(filepath.Join("..", "..", "resources", "fonts", "pressstart2p.ttf"))
-	if err != nil {
-		log.Fatal(err)
-	}
-	defer f.Close()
-
-	b, err := ioutil.ReadAll(f)
+	b, err := os.ReadFile(filepath.Join("..", "..", "resources", "fonts", "pressstart2p.ttf"))
 	if err != nil {
 		log.Fatal(err)
 	}
diff --git a/internal/gamepad/gamepad_linux.go b/internal/gamepad/gamepad_linux.go
index 3e3941dc6..dd413f49f 100644
--- a/internal/gamepad/gamepad_linux.go
+++ b/internal/gamepad/gamepad_linux.go
@@ -19,7 +19,7 @@ package gamepad
 
 import (
 	"fmt"
-	"io/ioutil"
+	"os"
 	"path/filepath"
 	"regexp"
 	"runtime"
@@ -77,7 +77,7 @@ func (g *nativeGamepadsImpl) init(gamepads *gamepads) error {
 		g.watch = watch
 	}
 
-	ents, err := ioutil.ReadDir(dirName)
+	ents, err := os.ReadDir(dirName)
 	if err != nil {
 		return fmt.Errorf("gamepad: ReadDir(%s) failed: %w", dirName, err)
 	}
diff --git a/internal/png/gen.go b/internal/png/gen.go
index 5412a6753..b2502586a 100644
--- a/internal/png/gen.go
+++ b/internal/png/gen.go
@@ -23,7 +23,6 @@ import (
 	"go/format"
 	"go/parser"
 	"go/token"
-	"io/ioutil"
 	"os"
 	"os/exec"
 	"path/filepath"
@@ -72,12 +71,6 @@ func run() error {
 	}
 
 	for _, f := range files {
-		in, err := os.Open(filepath.Join(dir, f))
-		if err != nil {
-			return err
-		}
-		defer in.Close()
-
 		out, err := os.Create(prefix + f)
 		if err != nil {
 			return err
@@ -86,7 +79,7 @@ func run() error {
 
 		// TODO: Remove call of RegisterDecoder
 
-		data, err := ioutil.ReadAll(in)
+		data, err := os.ReadFile(filepath.Join(dir, f))
 		if err != nil {
 			return err
 		}
diff --git a/internal/processtest/processtest_test.go b/internal/processtest/processtest_test.go
index 5a459416b..66c27cf0a 100644
--- a/internal/processtest/processtest_test.go
+++ b/internal/processtest/processtest_test.go
@@ -19,7 +19,7 @@ package processtest_test
 
 import (
 	"bytes"
-	"io/ioutil"
+	"os"
 	"os/exec"
 	"path/filepath"
 	"strings"
@@ -28,7 +28,7 @@ import (
 
 func TestPrograms(t *testing.T) {
 	dir := "testdata"
-	ents, err := ioutil.ReadDir(dir)
+	ents, err := os.ReadDir(dir)
 	if err != nil {
 		t.Fatal(err)
 	}
diff --git a/internal/shader/shader_test.go b/internal/shader/shader_test.go
index bee484c69..5360ec2fe 100644
--- a/internal/shader/shader_test.go
+++ b/internal/shader/shader_test.go
@@ -18,7 +18,7 @@ import (
 	"fmt"
 	"go/parser"
 	"go/token"
-	"io/ioutil"
+	"os"
 	"path/filepath"
 	"runtime"
 	"strings"
@@ -86,7 +86,7 @@ func TestCompile(t *testing.T) {
 		t.Skip("file open might not be implemented in this environment")
 	}
 
-	files, err := ioutil.ReadDir("testdata")
+	files, err := os.ReadDir("testdata")
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -114,7 +114,7 @@ func TestCompile(t *testing.T) {
 			continue
 		}
 
-		src, err := ioutil.ReadFile(filepath.Join("testdata", n))
+		src, err := os.ReadFile(filepath.Join("testdata", n))
 		if err != nil {
 			t.Fatal(err)
 		}
@@ -127,7 +127,7 @@ func TestCompile(t *testing.T) {
 
 		vsn := name + ".expected.vs"
 		if _, ok := fnames[vsn]; ok {
-			vs, err := ioutil.ReadFile(filepath.Join("testdata", vsn))
+			vs, err := os.ReadFile(filepath.Join("testdata", vsn))
 			if err != nil {
 				t.Fatal(err)
 			}
@@ -136,7 +136,7 @@ func TestCompile(t *testing.T) {
 
 		fsn := name + ".expected.fs"
 		if _, ok := fnames[fsn]; ok {
-			fs, err := ioutil.ReadFile(filepath.Join("testdata", fsn))
+			fs, err := os.ReadFile(filepath.Join("testdata", fsn))
 			if err != nil {
 				t.Fatal(err)
 			}
@@ -149,7 +149,7 @@ func TestCompile(t *testing.T) {
 
 		hlsln := name + ".expected.hlsl"
 		if _, ok := fnames[hlsln]; ok {
-			hlsl, err := ioutil.ReadFile(filepath.Join("testdata", hlsln))
+			hlsl, err := os.ReadFile(filepath.Join("testdata", hlsln))
 			if err != nil {
 				t.Fatal(err)
 			}
@@ -158,7 +158,7 @@ func TestCompile(t *testing.T) {
 
 		metaln := name + ".expected.metal"
 		if _, ok := fnames[metaln]; ok {
-			metal, err := ioutil.ReadFile(filepath.Join("testdata", metaln))
+			metal, err := os.ReadFile(filepath.Join("testdata", metaln))
 			if err != nil {
 				t.Fatal(err)
 			}