diff --git a/src/main/java/racal/sunyard/main/SydApi4j.java b/src/main/java/racal/sunyard/main/SydApi4j.java
index 73c6d25..c8ee979 100644
--- a/src/main/java/racal/sunyard/main/SydApi4j.java
+++ b/src/main/java/racal/sunyard/main/SydApi4j.java
@@ -641,6 +641,7 @@ public class SydApi4j implements SydApi {
         byte[] dn = new byte[256];
         byte[] s = null;
         try {
+            sCertDN = DnUtil.verifyDn( sCertDN );
             s = sCertDN.getBytes("GBK");
         } catch (UnsupportedEncodingException e) {
             e.printStackTrace();
@@ -10561,6 +10562,7 @@ public class SydApi4j implements SydApi {
     }
 
     public String attachedSignSoft(byte[] orgData, String sCertDN) throws UnsupportedEncodingException {
+        sCertDN = DnUtil.verifyDn( sCertDN );
         String pk = this.GetDNPublicKey( SydApi.FOR_SIGN, sCertDN.getBytes("GBK") );
         try {
             byte[] hash = this.SM3Hash( pk, orgData );