diff --git a/dubbo-registry-multicast/src/main/java/com/alibaba/dubbo/registry/multicast/MulticastRegistry.java b/dubbo-registry-multicast/src/main/java/com/alibaba/dubbo/registry/multicast/MulticastRegistry.java
index 54b2ba470c22525275c72739cc2739627be4174d..c65c70c676bb3696039f6fecf9dac49497aeb696 100644
--- a/dubbo-registry-multicast/src/main/java/com/alibaba/dubbo/registry/multicast/MulticastRegistry.java
+++ b/dubbo-registry-multicast/src/main/java/com/alibaba/dubbo/registry/multicast/MulticastRegistry.java
@@ -48,7 +48,9 @@ public class MulticastRegistry extends FailbackRegistry {
 
     // 日志输出
     private static final Logger logger = LoggerFactory.getLogger(MulticastRegistry.class);
-    
+
+    private static final int DEFAULT_MULTICAST_PORT = 1234;
+
     private static final String REGISTER = "register";
 
     private static final String UNREGISTER = "unregister";
@@ -70,7 +72,7 @@ public class MulticastRegistry extends FailbackRegistry {
         }
         try {
             mutilcastAddress = InetAddress.getByName(url.getHost());
-            mutilcastSocket = new MulticastSocket(url.getPort());
+            mutilcastSocket = new MulticastSocket(url.getPort() == 0 ? DEFAULT_MULTICAST_PORT : url.getPort());
             mutilcastSocket.setLoopbackMode(false);
             mutilcastSocket.joinGroup(mutilcastAddress);
             Thread thread = new Thread(new Runnable() {
@@ -299,4 +301,8 @@ public class MulticastRegistry extends FailbackRegistry {
         return notified;
     }
 
+    public MulticastSocket getMutilcastSocket() {
+        return mutilcastSocket;
+    }
+
 }
\ No newline at end of file
diff --git a/dubbo-registry-multicast/src/test/java/com/alibaba/dubbo/registry/multicast/MulticastRegistryTest.java b/dubbo-registry-multicast/src/test/java/com/alibaba/dubbo/registry/multicast/MulticastRegistryTest.java
index 3bd8cbec8253112da5d79052e2fe6b7f578f757c..3e1f8f0a87e8ca0e0de3d866ac60c97d3d4d0da3 100644
--- a/dubbo-registry-multicast/src/test/java/com/alibaba/dubbo/registry/multicast/MulticastRegistryTest.java
+++ b/dubbo-registry-multicast/src/test/java/com/alibaba/dubbo/registry/multicast/MulticastRegistryTest.java
@@ -18,11 +18,14 @@ package com.alibaba.dubbo.registry.multicast;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertTrue;
 
+import java.net.MulticastSocket;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
 import java.util.concurrent.atomic.AtomicReference;
 
+import junit.framework.Assert;
+
 import org.junit.Before;
 import org.junit.BeforeClass;
 import org.junit.Test;
@@ -107,4 +110,15 @@ public class MulticastRegistryTest {
 
     }
 
+    @Test
+    public void testDefaultPort() {
+        MulticastRegistry multicastRegistry = new MulticastRegistry(URL.valueOf("multicast://224.5.6.7"));
+        try {
+            MulticastSocket multicastSocket = multicastRegistry.getMutilcastSocket();
+            Assert.assertEquals(1234, multicastSocket.getLocalPort());
+        } finally {
+            multicastRegistry.destroy();
+        }
+    }
+
 }
\ No newline at end of file
diff --git a/dubbo-registry-zookeeper/src/main/java/com/alibaba/dubbo/registry/zookeeper/ZookeeperRegistry.java b/dubbo-registry-zookeeper/src/main/java/com/alibaba/dubbo/registry/zookeeper/ZookeeperRegistry.java
index ca6d00be1239278a7b9029ff94747c59104dbe50..540b70ad37ce731ef66ed4d0dc322385d6e88229 100644
--- a/dubbo-registry-zookeeper/src/main/java/com/alibaba/dubbo/registry/zookeeper/ZookeeperRegistry.java
+++ b/dubbo-registry-zookeeper/src/main/java/com/alibaba/dubbo/registry/zookeeper/ZookeeperRegistry.java
@@ -54,6 +54,8 @@ import com.alibaba.dubbo.rpc.RpcException;
 public class ZookeeperRegistry extends FailbackRegistry {
 
     private final static Logger logger = LoggerFactory.getLogger(ZookeeperRegistry.class);
+
+    private final static int DEFAULT_ZOOKEEPER_PORT = 2181;
     
     private final static int DEFAULT_SESSION_TIMEOUT = 60 * 1000;
     
@@ -151,14 +153,29 @@ public class ZookeeperRegistry extends FailbackRegistry {
         }
     }
     
+    static String appendDefaultPort(String address) {
+        if (address != null && address.length() > 0) {
+            int i = address.indexOf(':');
+            if (i < 0) {
+                return address + ":" + DEFAULT_ZOOKEEPER_PORT;
+            } else if (Integer.parseInt(address.substring(i + 1)) == 0) {
+                return address.substring(0, i + 1) + DEFAULT_ZOOKEEPER_PORT;
+            }
+        }
+        return address;
+    }
+    
     private ZooKeeper createZookeeper() throws Exception {
         URL url = getUrl();
-        String address = url.getAddress();
-        String backup = url.getParameter(Constants.BACKUP_KEY);
-        if (backup != null && backup.length() > 0) {
-            address = address + "," + backup;
+        StringBuilder address = new StringBuilder(appendDefaultPort(url.getAddress()));
+        String[] backups = url.getParameter(Constants.BACKUP_KEY, new String[0]);
+        if (backups != null && backups.length > 0) {
+            for (String backup : backups) {
+                address.append(",");
+                address.append(appendDefaultPort(backup));
+            }
         }
-        ZooKeeper zk = new ZooKeeper(address, url.getPositiveParameter(
+        ZooKeeper zk = new ZooKeeper(address.toString(), url.getPositiveParameter(
                 Constants.TIMEOUT_KEY, DEFAULT_SESSION_TIMEOUT), new Watcher() {
             public void process(WatchedEvent event) {
                 try {
diff --git a/dubbo-registry-zookeeper/src/test/java/com/alibaba/dubbo/registry/zookeeper/ZookeeperRegistryTest.java b/dubbo-registry-zookeeper/src/test/java/com/alibaba/dubbo/registry/zookeeper/ZookeeperRegistryTest.java
index a7baea3aac2826e598f5dc1ab56fe297405c0571..79f89a0cb3e63034e273e6830b184b11858ee40a 100644
--- a/dubbo-registry-zookeeper/src/test/java/com/alibaba/dubbo/registry/zookeeper/ZookeeperRegistryTest.java
+++ b/dubbo-registry-zookeeper/src/test/java/com/alibaba/dubbo/registry/zookeeper/ZookeeperRegistryTest.java
@@ -15,6 +15,8 @@
  */
 package com.alibaba.dubbo.registry.zookeeper;
 
+import junit.framework.Assert;
+
 import org.junit.Before;
 import org.junit.BeforeClass;
 import org.junit.Test;
@@ -55,6 +57,12 @@ public class ZookeeperRegistryTest {
         URL errorUrl = URL.valueOf("zookeeper://zookeeper/");
         new ZookeeperRegistry(errorUrl);
     }
+    
+    @Test
+    public void testDefaultPort() {
+        Assert.assertEquals("10.20.153.10:2181", ZookeeperRegistry.appendDefaultPort("10.20.153.10:0"));
+        Assert.assertEquals("10.20.153.10:2181", ZookeeperRegistry.appendDefaultPort("10.20.153.10"));
+    }
 
     /**
      * Test method for {@link com.alibaba.dubbo.registry.support.injvm.InjvmRegistry#register(java.util.Map)}.