diff --git a/CHANGELOG.md b/CHANGELOG.md
index 12a79a2a5..30275df37 100755
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -20,6 +20,7 @@
 * 【core   】      优化NumberUtil.count（pr#3772@Github）
 * 【crypto 】      SM2.signHex改名为signHexFromHex，原名标记废弃，避免歧义（issue#IB0NVY@Gitee）
 * 【all    】      优化所调用的ObjectUtil#defaultIfNull避免重复创建（pr#1274@Gitee）
+* 【core   】      NetUtil.bigIntegerToIPv6增加长度修正（issue#IB27HV@Gitee）
 
 ### 🐞Bug修复
 * 【json   】      修复JSONConfig.setDateFormat设置后toBean无效问题（issue#3713@Github）
diff --git a/hutool-core/src/main/java/cn/hutool/core/net/NetUtil.java b/hutool-core/src/main/java/cn/hutool/core/net/NetUtil.java
index 720e6bc3a..cc135fa2e 100755
--- a/hutool-core/src/main/java/cn/hutool/core/net/NetUtil.java
+++ b/hutool-core/src/main/java/cn/hutool/core/net/NetUtil.java
@@ -108,9 +108,30 @@ public class NetUtil {
 	 * @since 5.5.7
 	 */
 	public static String bigIntegerToIPv6(BigInteger bigInteger) {
+		// 确保 BigInteger 在 IPv6 地址范围内
+		if (bigInteger.compareTo(BigInteger.ZERO) < 0 || bigInteger.compareTo(new BigInteger("FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF", 16)) > 0) {
+			throw new IllegalArgumentException("BigInteger value is out of IPv6 range");
+		}
+
+		// 将 BigInteger 转换为 16 字节的字节数组
+		byte[] bytes = bigInteger.toByteArray();
+		if (bytes.length > 16) {
+			// 如果字节数组长度大于 16，去掉前导零
+			int offset = bytes[0] == 0 ? 1 : 0;
+			final byte[] newBytes = new byte[16];
+			System.arraycopy(bytes, offset, newBytes, 0, 16);
+			bytes = newBytes;
+		} else if (bytes.length < 16) {
+			// 如果字节数组长度小于 16，前面补零
+			byte[] paddedBytes = new byte[16];
+			System.arraycopy(bytes, 0, paddedBytes, 16 - bytes.length, bytes.length);
+			bytes = paddedBytes;
+		}
+
+		// 将字节数组转换为 IPv6 地址字符串
 		try {
-			return InetAddress.getByAddress(bigInteger.toByteArray()).toString().substring(1);
-		} catch (UnknownHostException ignore) {
+			return Inet6Address.getByAddress(bytes).getHostAddress();
+		} catch (UnknownHostException e) {
 			return null;
 		}
 	}
diff --git a/hutool-core/src/test/java/cn/hutool/core/net/NetUtilTest.java b/hutool-core/src/test/java/cn/hutool/core/net/NetUtilTest.java
index d64b567e5..803eeae92 100755
--- a/hutool-core/src/test/java/cn/hutool/core/net/NetUtilTest.java
+++ b/hutool-core/src/test/java/cn/hutool/core/net/NetUtilTest.java
@@ -3,15 +3,18 @@ package cn.hutool.core.net;
 import cn.hutool.core.lang.Console;
 import cn.hutool.core.lang.PatternPool;
 import cn.hutool.core.util.ReUtil;
-import static org.junit.jupiter.api.Assertions.*;
+import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.Disabled;
 import org.junit.jupiter.api.Test;
 
+import java.math.BigInteger;
 import java.net.HttpCookie;
 import java.net.InetAddress;
 import java.net.InetSocketAddress;
 import java.util.List;
 
+import static org.junit.jupiter.api.Assertions.*;
+
 /**
  * NetUtil单元测试
  *
@@ -126,4 +129,11 @@ public class NetUtilTest {
 		final String ip = NetUtil.getMultistageReverseProxyIp(ips);
 		assertEquals("12.34.56.78", ip);
 	}
+
+	@Test
+	void bigIntegerToIPv6Test() {
+		BigInteger bigInteger = new BigInteger("21987654321098765432109876543210", 10);
+		String ipv6Address = NetUtil.bigIntegerToIPv6(bigInteger);
+		Assertions.assertEquals("0:115:85f1:5eb3:c74d:a870:11c6:7eea", ipv6Address);
+	}
 }