diff --git a/CHANGELOG.md b/CHANGELOG.md
index 7a5ed7763..fce51e6fc 100755
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -12,6 +12,7 @@
 * 【json   】      JSONConfig增加setWriteLongAsString可选是否将Long写出为String类型（issue#3541@Github）
 * 【cache  】      CacheUtil.newTimedCache增加有schedulePruneDelay参数的重载方法（issue#I9HO25@Gitee）
 * 【core   】      NumberChineseFormatter提供阿拉伯转中文支持多位小数的方法（pr#3552@Github）
+* 【captcha】      Captcha.setBackground为null时背景透明（issue#3558@Github）
 
 ### 🐞Bug修复
 * 【http   】      修复HttpUtil.urlWithFormUrlEncoded方法重复编码问题（issue#3536@Github）
diff --git a/hutool-captcha/src/main/java/cn/hutool/captcha/AbstractCaptcha.java b/hutool-captcha/src/main/java/cn/hutool/captcha/AbstractCaptcha.java
index 7c4d0ee4c..adb48c32e 100755
--- a/hutool-captcha/src/main/java/cn/hutool/captcha/AbstractCaptcha.java
+++ b/hutool-captcha/src/main/java/cn/hutool/captcha/AbstractCaptcha.java
@@ -60,7 +60,7 @@ public abstract class AbstractCaptcha implements ICaptcha {
 	/**
 	 * 背景色
 	 */
-	protected Color background;
+	protected Color background = Color.WHITE;
 	/**
 	 * 文字透明度
 	 */
diff --git a/hutool-captcha/src/main/java/cn/hutool/captcha/CircleCaptcha.java b/hutool-captcha/src/main/java/cn/hutool/captcha/CircleCaptcha.java
index 27e24bc0e..7f6cf2ed1 100755
--- a/hutool-captcha/src/main/java/cn/hutool/captcha/CircleCaptcha.java
+++ b/hutool-captcha/src/main/java/cn/hutool/captcha/CircleCaptcha.java
@@ -82,8 +82,8 @@ public class CircleCaptcha extends AbstractCaptcha {
 
 	@Override
 	public Image createImage(String code) {
-		final BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
-		final Graphics2D g = ImgUtil.createGraphics(image, ObjectUtil.defaultIfNull(this.background, Color.WHITE));
+		final BufferedImage image = new BufferedImage(width, height, (null == this.background) ? BufferedImage.TYPE_4BYTE_ABGR : BufferedImage.TYPE_INT_RGB);
+		final Graphics2D g = ImgUtil.createGraphics(image, this.background);
 
 		try {
 			// 随机画干扰圈圈
diff --git a/hutool-captcha/src/main/java/cn/hutool/captcha/GifCaptcha.java b/hutool-captcha/src/main/java/cn/hutool/captcha/GifCaptcha.java
index ba86d6587..f6276967a 100755
--- a/hutool-captcha/src/main/java/cn/hutool/captcha/GifCaptcha.java
+++ b/hutool-captcha/src/main/java/cn/hutool/captcha/GifCaptcha.java
@@ -3,6 +3,7 @@ package cn.hutool.captcha;
 
 import cn.hutool.captcha.generator.CodeGenerator;
 import cn.hutool.captcha.generator.RandomGenerator;
+import cn.hutool.core.img.ImgUtil;
 import cn.hutool.core.img.gif.AnimatedGifEncoder;
 import cn.hutool.core.util.ObjectUtil;
 import cn.hutool.core.util.RandomUtil;
@@ -181,13 +182,11 @@ public class GifCaptcha extends AbstractCaptcha {
 	 * @return BufferedImage
 	 */
 	private BufferedImage graphicsImage(char[] chars, Color[] fontColor, char[] words, int flag) {
-		BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
+		final BufferedImage image = new BufferedImage(width, height, (null == this.background) ? BufferedImage.TYPE_4BYTE_ABGR : BufferedImage.TYPE_INT_RGB);
 		//或得图形上下文
-		Graphics2D g2d = image.createGraphics();
+		final Graphics2D g2d = ImgUtil.createGraphics(image, this.background);
 		try {
 			//利用指定颜色填充背景
-			g2d.setColor(ObjectUtil.defaultIfNull(this.background, Color.WHITE));
-			g2d.fillRect(0, 0, width, height);
 			AlphaComposite ac;
 			// 字符的y坐标
 			float y = (height >> 1) + (font.getSize() >> 1);
diff --git a/hutool-captcha/src/main/java/cn/hutool/captcha/LineCaptcha.java b/hutool-captcha/src/main/java/cn/hutool/captcha/LineCaptcha.java
index 197062a7e..55be796cf 100755
--- a/hutool-captcha/src/main/java/cn/hutool/captcha/LineCaptcha.java
+++ b/hutool-captcha/src/main/java/cn/hutool/captcha/LineCaptcha.java
@@ -74,8 +74,8 @@ public class LineCaptcha extends AbstractCaptcha {
 	@Override
 	public Image createImage(String code) {
 		// 图像buffer
-		final BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
-		final Graphics2D g = GraphicsUtil.createGraphics(image, ObjectUtil.defaultIfNull(this.background, Color.WHITE));
+		final BufferedImage image = new BufferedImage(width, height, (null == this.background) ? BufferedImage.TYPE_4BYTE_ABGR : BufferedImage.TYPE_INT_RGB);
+		final Graphics2D g = ImgUtil.createGraphics(image, this.background);
 
 		try {
 			// 干扰线
diff --git a/hutool-captcha/src/main/java/cn/hutool/captcha/ShearCaptcha.java b/hutool-captcha/src/main/java/cn/hutool/captcha/ShearCaptcha.java
index 7216837fd..f0c2a1482 100755
--- a/hutool-captcha/src/main/java/cn/hutool/captcha/ShearCaptcha.java
+++ b/hutool-captcha/src/main/java/cn/hutool/captcha/ShearCaptcha.java
@@ -84,8 +84,8 @@ public class ShearCaptcha extends AbstractCaptcha {
 
 	@Override
 	public Image createImage(String code) {
-		final BufferedImage image = new BufferedImage(this.width, this.height, BufferedImage.TYPE_INT_RGB);
-		final Graphics2D g = GraphicsUtil.createGraphics(image, ObjectUtil.defaultIfNull(this.background, Color.WHITE));
+		final BufferedImage image = new BufferedImage(width, height, (null == this.background) ? BufferedImage.TYPE_4BYTE_ABGR : BufferedImage.TYPE_INT_RGB);
+		final Graphics2D g = ImgUtil.createGraphics(image, this.background);
 
 		try{
 			// 画字符串
diff --git a/hutool-captcha/src/test/java/cn/hutool/captcha/CaptchaTest.java b/hutool-captcha/src/test/java/cn/hutool/captcha/CaptchaTest.java
index c1cef44c5..233635d01 100755
--- a/hutool-captcha/src/test/java/cn/hutool/captcha/CaptchaTest.java
+++ b/hutool-captcha/src/test/java/cn/hutool/captcha/CaptchaTest.java
@@ -28,8 +28,8 @@ public class CaptchaTest {
 	public void lineCaptchaTest3() {
 		// 定义图形验证码的长和宽
 		LineCaptcha lineCaptcha = CaptchaUtil.createLineCaptcha(200, 70, 4, 15);
-		lineCaptcha.setBackground(Color.yellow);
-		lineCaptcha.write("f:/test/captcha/tellow.png");
+		lineCaptcha.setBackground(null);
+		lineCaptcha.write("d:/test/captcha/tellow.png");
 	}
 
 	@Test