diff --git a/bcutils.js b/bcutils.js
index 9d39692..f293daa 100644
--- a/bcutils.js
+++ b/bcutils.js
@@ -112,6 +112,21 @@ function extractParamsFromTransId(transId) {
   return params;
 }
 
+function extractSubParams(param) {
+  const subParams = [0, 0];
+  if (param.toString().length <= 20) {
+    subParams[1] = param;
+  } else if (param.toString().length > 40) {
+    throw 'extractSubparams error to long:' + param;
+  } else {
+    subParams[0] = param.toString().substr(0, param.toString().length - 20);
+    subParams[1] = param.toString().substr(param.toString().length - 20);
+  }
+  subParams[0] = utils.removeLeadZero(subParams[0]);
+  subParams[1] = utils.removeLeadZero(subParams[1]);
+  return subParams;
+}
+
 function isEmptyAddress(address) {
   return address.toString().length < 10;
 }
@@ -152,5 +167,6 @@ exports.isSameAddress = isSameAddress;
 exports.genTransId = genTransId;
 exports.isValidTransId = isValidTransId;
 exports.extractParamsFromTransId = extractParamsFromTransId;
+exports.extractSubParams = extractSubParams;
 exports.isEmptyAddress = isEmptyAddress;
 exports.isValidAddress = isValidAddress;
diff --git a/utils.js b/utils.js
index 0e611e4..42b230f 100644
--- a/utils.js
+++ b/utils.js
@@ -319,7 +319,7 @@ function removeLeadZero(data) {
       return dataStr.substr(i);
     }
   }
-  return dataStr;
+  return 0;
 }
 
 exports.rspErr = rspErr;