diff --git a/weixin-java-cp/src/main/java/me/chanjar/weixin/cp/bean/WxCpTpUnionidToExternalUseridResult.java b/weixin-java-cp/src/main/java/me/chanjar/weixin/cp/bean/WxCpTpUnionidToExternalUseridResult.java
new file mode 100644
index 000000000..f14fa45f6
--- /dev/null
+++ b/weixin-java-cp/src/main/java/me/chanjar/weixin/cp/bean/WxCpTpUnionidToExternalUseridResult.java
@@ -0,0 +1,27 @@
+package me.chanjar.weixin.cp.bean;
+
+import com.google.gson.annotations.SerializedName;
+import lombok.*;
+import me.chanjar.weixin.cp.util.json.WxCpGsonBuilder;
+
+
+@Getter
+@Setter
+public class WxCpTpUnionidToExternalUseridResult extends WxCpBaseResp {
+
+
+  private static final long serialVersionUID = -6153589164415497369L;
+
+  @SerializedName("external_userid")
+  private String externalUserid;
+
+  @SerializedName("pending_id")
+  private String pendingId;
+
+
+  public static WxCpTpUnionidToExternalUseridResult fromJson(String json) {
+    return WxCpGsonBuilder.create().fromJson(json, WxCpTpUnionidToExternalUseridResult.class);
+  }
+
+
+}
diff --git a/weixin-java-cp/src/main/java/me/chanjar/weixin/cp/tp/service/WxCpTpIdConvertService.java b/weixin-java-cp/src/main/java/me/chanjar/weixin/cp/tp/service/WxCpTpIdConvertService.java
new file mode 100644
index 000000000..95979f628
--- /dev/null
+++ b/weixin-java-cp/src/main/java/me/chanjar/weixin/cp/tp/service/WxCpTpIdConvertService.java
@@ -0,0 +1,28 @@
+package me.chanjar.weixin.cp.tp.service;
+
+import me.chanjar.weixin.common.error.WxErrorException;
+import me.chanjar.weixin.cp.bean.WxCpTpUnionidToExternalUseridResult;
+
+/**
+ * <pre>
+ *  企业微信三方应用ID转换接口
+ *
+ * </pre>
+ *
+ * @author cocoa
+ */
+public interface WxCpTpIdConvertService {
+
+  /**
+   * unionid与external_userid的关联
+   * <a href="https://developer.work.weixin.qq.com/document/path/95900">查看文档</a>
+   *
+   * @param unionid     微信客户的unionid
+   * @param openid      微信客户的openid
+   * @param subjectType 程序或公众号的主体类型： 0表示主体名称是企业的，1表示主体名称是服务商的
+   * @throws WxErrorException 。
+   */
+  WxCpTpUnionidToExternalUseridResult unionidToExternalUserid(String cropId, String unionid, String openid,
+                                                              Integer subjectType) throws WxErrorException;
+
+}
diff --git a/weixin-java-cp/src/main/java/me/chanjar/weixin/cp/tp/service/WxCpTpService.java b/weixin-java-cp/src/main/java/me/chanjar/weixin/cp/tp/service/WxCpTpService.java
index e654ee9f2..6805d43b4 100644
--- a/weixin-java-cp/src/main/java/me/chanjar/weixin/cp/tp/service/WxCpTpService.java
+++ b/weixin-java-cp/src/main/java/me/chanjar/weixin/cp/tp/service/WxCpTpService.java
@@ -627,4 +627,10 @@ public interface WxCpTpService {
    * @param wxCpTpEditionService the wx cp tp edition service
    */
   void setWxCpTpOrderService(WxCpTpEditionService wxCpTpEditionService);
+
+
+  WxCpTpIdConvertService getWxCpTpIdConverService();
+
+  void setWxCpTpIdConverService(WxCpTpIdConvertService wxCpTpIdConvertService);
+
 }
diff --git a/weixin-java-cp/src/main/java/me/chanjar/weixin/cp/tp/service/impl/BaseWxCpTpServiceImpl.java b/weixin-java-cp/src/main/java/me/chanjar/weixin/cp/tp/service/impl/BaseWxCpTpServiceImpl.java
index 9d84b152e..2e3f08633 100644
--- a/weixin-java-cp/src/main/java/me/chanjar/weixin/cp/tp/service/impl/BaseWxCpTpServiceImpl.java
+++ b/weixin-java-cp/src/main/java/me/chanjar/weixin/cp/tp/service/impl/BaseWxCpTpServiceImpl.java
@@ -57,6 +57,7 @@ public abstract class BaseWxCpTpServiceImpl<H, P> implements WxCpTpService, Requ
   private WxCpTpOrderService wxCpTpOrderService = new WxCpTpOrderServiceImpl(this);
   private WxCpTpEditionService wxCpTpEditionService = new WxCpTpEditionServiceImpl(this);
   private WxCpTpLicenseService wxCpTpLicenseService = new WxCpTpLicenseServiceImpl(this);
+  private WxCpTpIdConvertService wxCpTpIdConvertService = new WxCpTpIdConvertServiceImpl(this);
 
   /**
    * 全局的是否正在刷新access token的锁.
@@ -743,4 +744,16 @@ public abstract class BaseWxCpTpServiceImpl<H, P> implements WxCpTpService, Requ
     return jsapiSignature;
   }
 
+  @Override
+  public WxCpTpIdConvertService getWxCpTpIdConverService() {
+    return wxCpTpIdConvertService;
+  }
+
+  @Override
+  public void setWxCpTpIdConverService(WxCpTpIdConvertService wxCpTpIdConvertService) {
+    this.wxCpTpIdConvertService = wxCpTpIdConvertService;
+  }
+
+
+
 }
diff --git a/weixin-java-cp/src/main/java/me/chanjar/weixin/cp/tp/service/impl/WxCpTpIdConvertServiceImpl.java b/weixin-java-cp/src/main/java/me/chanjar/weixin/cp/tp/service/impl/WxCpTpIdConvertServiceImpl.java
new file mode 100644
index 000000000..7692794a6
--- /dev/null
+++ b/weixin-java-cp/src/main/java/me/chanjar/weixin/cp/tp/service/impl/WxCpTpIdConvertServiceImpl.java
@@ -0,0 +1,36 @@
+package me.chanjar.weixin.cp.tp.service.impl;
+
+import com.google.gson.JsonObject;
+import lombok.RequiredArgsConstructor;
+import me.chanjar.weixin.common.error.WxErrorException;
+import me.chanjar.weixin.cp.bean.WxCpTpUnionidToExternalUseridResult;
+import me.chanjar.weixin.cp.config.WxCpTpConfigStorage;
+import me.chanjar.weixin.cp.tp.service.WxCpTpIdConvertService;
+import me.chanjar.weixin.cp.tp.service.WxCpTpService;
+
+
+/**
+ * @author cocoa
+ */
+@RequiredArgsConstructor
+public class WxCpTpIdConvertServiceImpl implements WxCpTpIdConvertService {
+  private final WxCpTpService mainService;
+
+  @Override
+  public WxCpTpUnionidToExternalUseridResult unionidToExternalUserid(String cropId, String unionid, String openid, Integer subjectType) throws WxErrorException {
+    JsonObject json = new JsonObject();
+    json.addProperty("unionid", unionid);
+    json.addProperty("openid", openid);
+    if (subjectType != null) {
+      json.addProperty("subject_type", subjectType);
+    }
+    WxCpTpConfigStorage wxCpTpConfigStorage = mainService.getWxCpTpConfigStorage();
+    String accessToken = wxCpTpConfigStorage.getAccessToken(cropId);
+    String url = wxCpTpConfigStorage.getApiUrl("/cgi-bin/idconvert/unionid_to_external_userid");
+    url += "?access_token=" + accessToken;
+    String responseContent = this.mainService.post(url, json.toString());
+    return WxCpTpUnionidToExternalUseridResult.fromJson(responseContent);
+  }
+
+
+}