diff --git a/weixin-java-cp/src/main/java/me/chanjar/weixin/cp/bean/message/WxCpXmlMessage.java b/weixin-java-cp/src/main/java/me/chanjar/weixin/cp/bean/message/WxCpXmlMessage.java
index e37229cf8e..c5e55220e5 100644
--- a/weixin-java-cp/src/main/java/me/chanjar/weixin/cp/bean/message/WxCpXmlMessage.java
+++ b/weixin-java-cp/src/main/java/me/chanjar/weixin/cp/bean/message/WxCpXmlMessage.java
@@ -92,7 +92,7 @@ public class WxCpXmlMessage implements Serializable {
   private String content;
 
   @XStreamAlias("MsgId")
-  private Long msgId;
+  private String msgId;
 
   @XStreamAlias("PicUrl")
   @XStreamConverter(value = XStreamCDataConverter.class)
diff --git a/weixin-java-cp/src/test/java/me/chanjar/weixin/cp/bean/message/WxCpXmlMessageTest.java b/weixin-java-cp/src/test/java/me/chanjar/weixin/cp/bean/message/WxCpXmlMessageTest.java
index 5bcfe9698a..ae4fbba8f6 100644
--- a/weixin-java-cp/src/test/java/me/chanjar/weixin/cp/bean/message/WxCpXmlMessageTest.java
+++ b/weixin-java-cp/src/test/java/me/chanjar/weixin/cp/bean/message/WxCpXmlMessageTest.java
@@ -72,7 +72,7 @@ public void testFromXml() {
     assertEquals(wxMessage.getCreateTime(), Long.valueOf(1348831860));
     assertEquals(wxMessage.getMsgType(), WxConsts.XmlMsgType.TEXT);
     assertEquals(wxMessage.getContent(), "this is a test");
-    assertEquals(wxMessage.getMsgId(), Long.valueOf(1234567890123456L));
+    assertEquals(wxMessage.getMsgId(), "1234567890123456");
     assertEquals(wxMessage.getPicUrl(), "this is a url");
     assertEquals(wxMessage.getMediaId(), "media_id");
     assertEquals(wxMessage.getFormat(), "Format");
@@ -442,4 +442,33 @@ public void testUploadMediaJobFinishEvent() {
     assertThat(wxCpXmlMessage.getJobId()).isEqualTo("jobid_S0MrnndvRG5fadSlLwiBqiDDbM143UqTmKP3152FZk4");
     assertThat(wxCpXmlMessage.getEvent()).isEqualTo(UPLOAD_MEDIA_JOB_FINISH);
   }
+
+  /**
+   * Test both numeric and string msgId formats to ensure backward compatibility
+   */
+  public void testMsgIdStringAndNumericFormats() {
+    // Test with numeric msgId (old format)
+    String xmlWithNumeric = "<xml>"
+      + "<ToUserName><![CDATA[toUser]]></ToUserName>"
+      + "<FromUserName><![CDATA[fromUser]]></FromUserName>"
+      + "<CreateTime>1348831860</CreateTime>"
+      + "<MsgType><![CDATA[text]]></MsgType>"
+      + "<Content><![CDATA[this is a test]]></Content>"
+      + "<MsgId>1234567890123456</MsgId>"
+      + "</xml>";
+    WxCpXmlMessage wxMessageNumeric = WxCpXmlMessage.fromXml(xmlWithNumeric);
+    assertEquals(wxMessageNumeric.getMsgId(), "1234567890123456");
+
+    // Test with string msgId (new format - the actual issue case)
+    String xmlWithString = "<xml>"
+      + "<ToUserName><![CDATA[toUser]]></ToUserName>"
+      + "<FromUserName><![CDATA[fromUser]]></FromUserName>"
+      + "<CreateTime>1348831860</CreateTime>"
+      + "<MsgType><![CDATA[text]]></MsgType>"
+      + "<Content><![CDATA[this is a test]]></Content>"
+      + "<MsgId>CAIQg/PKxgYY2sC9tpuAgAMg9/zKaw==</MsgId>"
+      + "</xml>";
+    WxCpXmlMessage wxMessageString = WxCpXmlMessage.fromXml(xmlWithString);
+    assertEquals(wxMessageString.getMsgId(), "CAIQg/PKxgYY2sC9tpuAgAMg9/zKaw==");
+  }
 }