diff --git a/src/main/java/com/github/ontio/crypto/Signature.java b/src/main/java/com/github/ontio/crypto/Signature.java
index 51ec4ad0..29e9cf44 100644
--- a/src/main/java/com/github/ontio/crypto/Signature.java
+++ b/src/main/java/com/github/ontio/crypto/Signature.java
@@ -27,24 +27,16 @@ public Signature(byte[] data) throws Exception {
             throw new SDKException(ErrorCode.ParamError);
         }
 
-        if (data.length == 65) {
-            SignatureScheme[] schemes = SignatureScheme.values();
-            if (data[0] > schemes.length) {
-                throw new SDKException(ErrorCode.UnsupportedSignatureScheme);
-            }
-            this.scheme = schemes[data[0]];
-        } else if (data.length == 64) { // use default scheme
-            byte[] temp = new byte[65];
-            temp[0] = 1;
-            System.arraycopy(data, 0, temp, 1, 64);
-            data = temp;
+        if (data.length == 64) {
+            this.value = data;
             this.scheme = SignatureScheme.SHA256WITHECDSA;
-        } else {
-            throw new Exception(ErrorCode.InvalidSignatureDataLen);
+            return;
         }
+
+        this.scheme = SignatureScheme.values()[data[0]];
         if (scheme == SignatureScheme.SM3WITHSM2) {
             int i = 0;
-            while (i < data.length && data[i] != 0) {
+            while (i < data.length && data[i] != 0){
                 i++;
             }
             if (i >= data.length) {
diff --git a/src/test/java/com/github/ontio/account/AccountTest.java b/src/test/java/com/github/ontio/account/AccountTest.java
index b74f3cd5..25b2db20 100644
--- a/src/test/java/com/github/ontio/account/AccountTest.java
+++ b/src/test/java/com/github/ontio/account/AccountTest.java
@@ -11,9 +11,17 @@ public class AccountTest {
 
     @Test
     public void generateSignature() throws Exception {
+        Account account = new Account(SignatureScheme.SM3WITHSM2);
+        byte[] signature = account.generateSignature("hello".getBytes(), SignatureScheme.SM3WITHSM2, null);
+        boolean b = account.verifySignature("hello".getBytes(), signature);
+        assertTrue(b);
+    }
+
+    @Test
+    public void testSHA256WITHECDSA() throws Exception {
         Account account = new Account(SignatureScheme.SHA256WITHECDSA);
-        byte[]  signature = account.generateSignature("hello".getBytes(),SignatureScheme.SHA256WITHECDSA,null);
-        boolean b = account.verifySignature("hello".getBytes(),signature);
+        byte[] signature = account.generateSignature("hello".getBytes(), SignatureScheme.SHA256WITHECDSA, null);
+        boolean b = account.verifySignature("hello".getBytes(), signature);
         assertTrue(b);
     }
 
@@ -42,9 +50,9 @@ public void compareTo() throws Exception {
     @Test
     public void exportCtrEncryptedPrikey1() throws Exception {
         Account account = new Account(SignatureScheme.SHA256WITHECDSA);
-        String encruPri = account.exportCtrEncryptedPrikey("111111",16384);
-        String privateKey = Account.getCtrDecodedPrivateKey(encruPri,"111111",account.getAddressU160().toBase58(),16384,SignatureScheme.SHA256WITHECDSA);
-        assertEquals(privateKey,Helper.toHexString(account.serializePrivateKey()));
+        String encruPri = account.exportCtrEncryptedPrikey("111111", 16384);
+        String privateKey = Account.getCtrDecodedPrivateKey(encruPri, "111111", account.getAddressU160().toBase58(), 16384, SignatureScheme.SHA256WITHECDSA);
+        assertEquals(privateKey, Helper.toHexString(account.serializePrivateKey()));
     }
 
 }
\ No newline at end of file