diff --git a/src/main/java/com/dispose/service/impl/ProtocolSecurityServiceImpl.java b/src/main/java/com/dispose/service/impl/ProtocolSecurityServiceImpl.java
index ac29af73..455a1ff8 100644
--- a/src/main/java/com/dispose/service/impl/ProtocolSecurityServiceImpl.java
+++ b/src/main/java/com/dispose/service/impl/ProtocolSecurityServiceImpl.java
@@ -71,7 +71,7 @@ public class ProtocolSecurityServiceImpl implements ProtocolSecurityService {
             decryptContent = base64Decode;
         } else if (proReq.getCryptoType() == ProtoCryptoType.CRYPTO_AES256.getCode()) {
             try {
-                decryptContent = CryptoHelper.aes256Decryption(base64Decode, SecurityConfigValue.AES_KEY);
+                decryptContent = CryptoHelper.aes128Decryption(base64Decode, SecurityConfigValue.AES_KEY);
             } catch (Exception e) {
                 log.error("AES256 decode message error: {}", base64Decode);
                 throw new SecurityProtocolException(ErrorCode.ERR_DECRYPT_AES256);
@@ -123,7 +123,7 @@ public class ProtocolSecurityServiceImpl implements ProtocolSecurityService {
             cipherText = CryptoHelper.base64Encryption(plainText.getBytes(StandardCharsets.UTF_8));
         } else if (cryptoType == ProtoCryptoType.CRYPTO_AES256.getCode()) {
             try {
-                byte[] encode = CryptoHelper.aes256Encryption(plainText.getBytes(StandardCharsets.UTF_8),
+                byte[] encode = CryptoHelper.aes128Encryption(plainText.getBytes(StandardCharsets.UTF_8),
                                                               SecurityConfigValue.AES_KEY);
                 cipherText = CryptoHelper.base64Encryption(encode);
             } catch (Exception e) {
diff --git a/src/main/java/com/security/arithmetic/CryptoHelper.java b/src/main/java/com/security/arithmetic/CryptoHelper.java
index 2ac8652f..0582233c 100644
--- a/src/main/java/com/security/arithmetic/CryptoHelper.java
+++ b/src/main/java/com/security/arithmetic/CryptoHelper.java
@@ -82,13 +82,13 @@ public class CryptoHelper {
      * @throws BadPaddingException       the bad padding exception
      * @throws IllegalBlockSizeException the illegal block size exception
      */
-    public static byte[] aes256Encryption(byte[] plaintext, String aesKey) throws NoSuchAlgorithmException,
+    public static byte[] aes128Encryption(byte[] plaintext, String aesKey) throws NoSuchAlgorithmException,
         NoSuchPaddingException, InvalidKeyException, BadPaddingException, IllegalBlockSizeException {
         KeyGenerator keyGen = KeyGenerator.getInstance("AES");
         SecureRandom secureRandom = SecureRandom.getInstance("SHA1PRNG");
-        secureRandom.setSeed(sha256Encryption(aesKey));
+        secureRandom.setSeed(aesKey.getBytes());
 
-        keyGen.init(256, secureRandom);
+        keyGen.init(128, secureRandom);
         Cipher cipher = Cipher.getInstance(AES_ALGORITHM_STR);
         SecretKeySpec key = new SecretKeySpec(keyGen.generateKey().getEncoded(), "AES");
         cipher.init(Cipher.ENCRYPT_MODE, key);
@@ -107,13 +107,13 @@ public class CryptoHelper {
      * @throws BadPaddingException       the bad padding exception
      * @throws IllegalBlockSizeException the illegal block size exception
      */
-    public static byte[] aes256Decryption(byte[] ciphertext, String aesKey) throws NoSuchAlgorithmException,
+    public static byte[] aes128Decryption(byte[] ciphertext, String aesKey) throws NoSuchAlgorithmException,
         NoSuchPaddingException, InvalidKeyException, BadPaddingException, IllegalBlockSizeException {
         KeyGenerator keyGen = KeyGenerator.getInstance("AES");
         SecureRandom secureRandom = SecureRandom.getInstance("SHA1PRNG");
-        secureRandom.setSeed(sha256Encryption(aesKey));
+        secureRandom.setSeed(aesKey.getBytes());
 
-        keyGen.init(256, secureRandom);
+        keyGen.init(128, secureRandom);
         Cipher cipher = Cipher.getInstance(AES_ALGORITHM_STR);
         SecretKeySpec key = new SecretKeySpec(keyGen.generateKey().getEncoded(), "AES");
         cipher.init(Cipher.DECRYPT_MODE, key);