diff --git a/src/main/java/racal/sunyard/main/SydApi4j.java b/src/main/java/racal/sunyard/main/SydApi4j.java
index 5cd7f72..8212e56 100644
--- a/src/main/java/racal/sunyard/main/SydApi4j.java
+++ b/src/main/java/racal/sunyard/main/SydApi4j.java
@@ -7059,6 +7059,7 @@ public class SydApi4j implements SydApi {
         bb.put((byte) dataType);
 
         if (dataType == 2) {                 // 私钥
+            bb.put("999999999999999999999999999".getBytes());
             bb.put(ByteUtil.shortToBytes((short) privateKey.length, ByteOrder.BIG_ENDIAN));
             bb.put(privateKey);
         }
diff --git a/src/test/java/cmbpoc/FunctionTest.java b/src/test/java/cmbpoc/FunctionTest.java
index 4721d34..703be55 100644
--- a/src/test/java/cmbpoc/FunctionTest.java
+++ b/src/test/java/cmbpoc/FunctionTest.java
@@ -99,8 +99,9 @@ public class FunctionTest {
     @Test
     public void SYD_SM2_Encrypt(){
         byte[] enData = this.api.SYD_SM2Encrypt(publicKey4Ende, orgData);
-//        byte[] deData = this.api.SYD_SM2Decrypt(publicKey4Ende, enData);
-//        Assert.assertArrayEquals(enData, deData);
+        System.out.println("密文=" + Util.bytes2HexString(enData));
+        byte[] deData = this.api.SYD_SM2Decrypt(privateKey4Ende, enData);
+        Assert.assertArrayEquals(orgData, deData);
     }
 }