diff --git a/lib/hdprivatekey.js b/lib/hdprivatekey.js
index ad53e1c6a..c3f85a5ab 100644
--- a/lib/hdprivatekey.js
+++ b/lib/hdprivatekey.js
@@ -41,25 +41,25 @@ function HDPrivateKey(arg) {
   if (!(this instanceof HDPrivateKey)) {
     return new HDPrivateKey(arg);
   }
-  if (arg) {
-    if (_.isString(arg) || BufferUtil.isBuffer(arg)) {
-      if (HDPrivateKey.isValidSerialized(arg)) {
-        this._buildFromSerialized(arg);
-      } else if (JSUtil.isValidJSON(arg)) {
-        this._buildFromJSON(arg);
-      } else {
-        throw HDPrivateKey.getSerializedError(arg);
-      }
-    } else {
-      if (_.isObject(arg)) {
-        this._buildFromObject(arg);
-      } else {
-        throw new hdErrors.UnrecognizedArgument(arg);
-      }
-    }
-  } else {
+  if (!arg) {
     return this._generateRandomly();
   }
+
+  if (Network.get(arg)) {
+    return this._generateRandomly(arg);
+  } else if (_.isString(arg) || BufferUtil.isBuffer(arg)) {
+    if (HDPrivateKey.isValidSerialized(arg)) {
+      this._buildFromSerialized(arg);
+    } else if (JSUtil.isValidJSON(arg)) {
+      this._buildFromJSON(arg);
+    } else {
+      throw HDPrivateKey.getSerializedError(arg);
+    }
+  } else if (_.isObject(arg)) {
+    this._buildFromObject(arg);
+  } else {
+    throw new hdErrors.UnrecognizedArgument(arg);
+  }
 }
 
 /**
@@ -266,7 +266,6 @@ HDPrivateKey.prototype._generateRandomly = function(network) {
  */
 HDPrivateKey.fromSeed = function(hexa, network) {
   /* jshint maxcomplexity: 8 */
-
   if (JSUtil.isHexaString(hexa)) {
     hexa = BufferUtil.hexToBuffer(hexa);
   }
@@ -282,7 +281,7 @@ HDPrivateKey.fromSeed = function(hexa, network) {
   var hash = Hash.sha512hmac(hexa, new buffer.Buffer('Bitcoin seed'));
 
   return new HDPrivateKey({
-    network: Network.get(network) || Network.livenet,
+    network: Network.get(network) || Network.defaultNetwork,
     depth: 0,
     parentFingerPrint: 0,
     childIndex: 0,
@@ -441,7 +440,6 @@ HDPrivateKey.prototype.toJSON = function toJSON() {
 HDPrivateKey.DefaultDepth = 0;
 HDPrivateKey.DefaultFingerprint = 0;
 HDPrivateKey.DefaultChildIndex = 0;
-HDPrivateKey.DefaultNetwork = Network.livenet;
 HDPrivateKey.Hardened = 0x80000000;
 HDPrivateKey.RootElementAlias = ['m', 'M', 'm\'', 'M\''];
 
diff --git a/test/hdprivatekey.js b/test/hdprivatekey.js
index 6ba3b4d67..d8779c7ab 100644
--- a/test/hdprivatekey.js
+++ b/test/hdprivatekey.js
@@ -50,6 +50,12 @@ describe('HDPrivate key interface', function() {
     should.exist(new HDPrivateKey().xprivkey);
   });
 
+  it('should make a new private key from random for testnet', function() {
+    var key = new HDPrivateKey('testnet');
+    should.exist(key.xprivkey);
+    key.network.name.should.equal('testnet');
+  });
+
   it('should not be able to change read-only properties', function() {
     var hdkey = new HDPrivateKey();
     expect(function() {