diff --git a/miniprogram/auth/auth.go b/miniprogram/auth/auth.go
index 147480a..848a3a1 100644
--- a/miniprogram/auth/auth.go
+++ b/miniprogram/auth/auth.go
@@ -10,11 +10,22 @@ import (
 )
 
 const (
+	// code2SessionURL 小程序登录
 	code2SessionURL = "https://api.weixin.qq.com/sns/jscode2session?appid=%s&secret=%s&js_code=%s&grant_type=authorization_code"
-
+	// checkEncryptedDataURL 检查加密信息
 	checkEncryptedDataURL = "https://api.weixin.qq.com/wxa/business/checkencryptedmsg?access_token=%s"
-
+	// getPhoneNumber 获取手机号
 	getPhoneNumber = "https://api.weixin.qq.com/wxa/business/getuserphonenumber?access_token=%s"
+	// checkSessionURL 检验登录态
+	checkSessionURL = "https://api.weixin.qq.com/wxa/checksession?access_token=%s&signature=%s&openid=%s&sig_method=hmac_sha256"
+	// resetUserSessionKeyURL 重置登录态
+	resetUserSessionKeyURL = "https://api.weixin.qq.com/wxa/resetusersessionkey?access_token=%s&signature=%s&openid=%s&sig_method=hmac_sha256"
+	// getPluginOpenPIDURL 获取插件用户openPID
+	getPluginOpenPIDURL = "https://api.weixin.qq.com/wxa/getpluginopenpid?access_token=%s"
+	// getPaidUnionIDURL 支付后获取 UnionID
+	getPaidUnionIDURL = "https://api.weixin.qq.com/wxa/getpaidunionid"
+	// getUserEncryptKeyURL 获取用户encryptKey
+	getUserEncryptKeyURL = "https://api.weixin.qq.com/wxa/business/getuserencryptkey?access_token=%s&signature=%s&openid=%s&sig_method=hmac_sha256"
 )
 
 // Auth 登录/用户信息
@@ -65,9 +76,45 @@ func (auth *Auth) Code2SessionContext(ctx context2.Context, jsCode string) (resu
 	return
 }
 
+type (
+	// GetPaidUnionIDRequest 支付后获取UnionID请求
+	GetPaidUnionIDRequest struct {
+		OpenID        string `json:"openid"`
+		TransactionID string `json:"transaction_id,omitempty"`
+		MchID         string `json:"mch_id,omitempty"`
+		OutTradeNo    string `json:"out_trade_no,omitempty"`
+	}
+
+	// GetPaidUnionIDResponse 支付后获取UnionID响应
+	GetPaidUnionIDResponse struct {
+		util.CommonError
+		UnionID string `json:"unionid"`
+	}
+)
+
 // GetPaidUnionID 用户支付完成后，获取该用户的 UnionId，无需用户授权
-func (auth *Auth) GetPaidUnionID() {
-	// TODO
+// see https://developers.weixin.qq.com/miniprogram/dev/OpenApiDoc/user-info/basic-info/getPaidUnionid.html
+func (auth *Auth) GetPaidUnionID(req *GetPaidUnionIDRequest) (string, error) {
+	var (
+		accessToken string
+		err         error
+	)
+	if accessToken, err = auth.GetAccessToken(); err != nil {
+		return "", err
+	}
+	var url string
+	if req.TransactionID != "" {
+		url = fmt.Sprintf("%s?access_token=%s&openid=%s&transaction_id=%s", getPaidUnionIDURL, accessToken, req.OpenID, req.TransactionID)
+	} else {
+		url = fmt.Sprintf("%s?access_token=%s&openid=%s&mch_id=%s&out_trade_no=%s", getPaidUnionIDURL, accessToken, req.OpenID, req.MchID, req.OutTradeNo)
+	}
+	var response []byte
+	if response, err = util.HTTPGet(url); err != nil {
+		return "", err
+	}
+	result := &GetPaidUnionIDResponse{}
+	err = util.DecodeWithError(response, result, "GetPaidUnionID")
+	return result.UnionID, err
 }
 
 // CheckEncryptedData .检查加密信息是否由微信生成（当前只支持手机号加密数据），只能检测最近3天生成的加密数据
@@ -146,3 +193,115 @@ func (auth *Auth) GetPhoneNumberContext(ctx context2.Context, code string) (*Get
 func (auth *Auth) GetPhoneNumber(code string) (*GetPhoneNumberResponse, error) {
 	return auth.GetPhoneNumberContext(context2.Background(), code)
 }
+
+// CheckSession 检验登录态
+// see https://developers.weixin.qq.com/miniprogram/dev/OpenApiDoc/user-login/checkSessionKey.html
+func (auth *Auth) CheckSession(signature, openID string) error {
+	var (
+		accessToken string
+		err         error
+	)
+	if accessToken, err = auth.GetAccessToken(); err != nil {
+		return err
+	}
+	var response []byte
+	if response, err = util.HTTPGet(fmt.Sprintf(checkSessionURL, accessToken, signature, openID)); err != nil {
+		return err
+	}
+	return util.DecodeWithCommonError(response, "CheckSession")
+}
+
+// ResetUserSessionKeyResponse 重置登录态响应
+type ResetUserSessionKeyResponse struct {
+	util.CommonError
+	OpenID     string `json:"openid"`
+	SessionKey string `json:"session_key"`
+}
+
+// ResetUserSessionKey 重置登录态
+// see https://developers.weixin.qq.com/miniprogram/dev/OpenApiDoc/user-login/ResetUserSessionKey.html
+func (auth *Auth) ResetUserSessionKey(signature, openID string) (*ResetUserSessionKeyResponse, error) {
+	var (
+		accessToken string
+		err         error
+	)
+	if accessToken, err = auth.GetAccessToken(); err != nil {
+		return nil, err
+	}
+	var response []byte
+	if response, err = util.HTTPGet(fmt.Sprintf(resetUserSessionKeyURL, accessToken, signature, openID)); err != nil {
+		return nil, err
+	}
+	result := &ResetUserSessionKeyResponse{}
+	err = util.DecodeWithError(response, result, "ResetUserSessionKey")
+	return result, err
+}
+
+type (
+	// GetPluginOpenPIDRequest 获取插件用户openPID请求
+	GetPluginOpenPIDRequest struct {
+		Code string `json:"code"`
+	}
+
+	// GetPluginOpenPIDResponse 获取插件用户openPID响应
+	GetPluginOpenPIDResponse struct {
+		util.CommonError
+		OpenPID string `json:"openpid"`
+	}
+)
+
+// GetPluginOpenPID 获取插件用户openPID
+// see https://developers.weixin.qq.com/miniprogram/dev/OpenApiDoc/user-info/basic-info/getPluginOpenPId.html
+func (auth *Auth) GetPluginOpenPID(code string) (string, error) {
+	var (
+		accessToken string
+		err         error
+	)
+	if accessToken, err = auth.GetAccessToken(); err != nil {
+		return "", err
+	}
+	req := &GetPluginOpenPIDRequest{
+		Code: code,
+	}
+	var response []byte
+	if response, err = util.PostJSON(fmt.Sprintf(getPluginOpenPIDURL, accessToken), req); err != nil {
+		return "", err
+	}
+	result := &GetPluginOpenPIDResponse{}
+	err = util.DecodeWithError(response, result, "GetPluginOpenPID")
+	return result.OpenPID, err
+}
+
+// GetUserEncryptKeyResponse 获取用户encryptKey响应
+type GetUserEncryptKeyResponse struct {
+	util.CommonError
+	KeyInfoList []KeyInfo `json:"key_info_list"`
+}
+
+// KeyInfo 用户最近三次的加密key
+type KeyInfo struct {
+	EncryptKey string `json:"encrypt_key"`
+	Version    int64  `json:"version"`
+	ExpireIn   int64  `json:"expire_in"`
+	Iv         string `json:"iv"`
+	CreateTime int64  `json:"create_time"`
+}
+
+// GetUserEncryptKey 获取用户encryptKey
+// see https://developers.weixin.qq.com/miniprogram/dev/OpenApiDoc/user-info/internet/getUserEncryptKey.html
+func (auth *Auth) GetUserEncryptKey(signature, openID string) (*GetUserEncryptKeyResponse, error) {
+	var (
+		accessToken string
+		err         error
+	)
+	if accessToken, err = auth.GetAccessToken(); err != nil {
+		return nil, err
+	}
+	var response []byte
+	if response, err = util.HTTPGet(fmt.Sprintf(getUserEncryptKeyURL, accessToken, signature, openID)); err != nil {
+		return nil, err
+	}
+	result := &GetUserEncryptKeyResponse{}
+	err = util.DecodeWithError(response, result, "GetUserEncryptKey")
+	return result, err
+}