diff --git a/lib/bip32.js b/lib/bip32.js
index a4e687619..e09d9f4f4 100644
--- a/lib/bip32.js
+++ b/lib/bip32.js
@@ -173,10 +173,7 @@ BIP32.prototype.buildExtendedPrivateKey = function() {
 
 BIP32.prototype.extendedPrivateKeyString = function(format) {
   if (format === undefined || format === 'base58') {
-    var hash = Hash.sha256sha256(this.extendedPrivateKey);
-    var checksum = hash.slice(0, 4);
-    var data = Buffer.concat([this.extendedPrivateKey, checksum]);
-    return base58.encode(data);
+    return Base58Check.encode(this.extendedPrivateKey);
   } else if (format === 'hex') {
     return this.extendedPrivateKey.toString('hex');
   } else {