diff --git a/models/wechat_bind.go b/models/wechat_bind.go
index f75188280..3cca4888a 100644
--- a/models/wechat_bind.go
+++ b/models/wechat_bind.go
@@ -47,6 +47,18 @@ func BindWechatOpenId(userId int64, wechatOpenId string) error {
 	return sess.Commit()
 }
 
+func GetUserWechatOpenId(userId int64) string {
+	param := &User{}
+	x.Cols("wechat_open_id").Where("ID =?", userId).Get(param)
+	return param.WechatOpenId
+}
+
+func GetUserByWechatOpenId(wechatOpenId string) *User {
+	user := &User{}
+	x.Where("wechat_open_id = ?", wechatOpenId).Get(user)
+	return user
+}
+
 func UnbindWechatOpenId(userId int64, oldWechatOpenID string) error {
 	sess := x.NewSession()
 	defer sess.Close()
diff --git a/modules/auth/wechat/bind.go b/modules/auth/wechat/bind.go
index 54937e4e1..a2172718a 100644
--- a/modules/auth/wechat/bind.go
+++ b/modules/auth/wechat/bind.go
@@ -2,6 +2,8 @@ package wechat
 
 import (
 	"code.gitea.io/gitea/models"
+	"code.gitea.io/gitea/modules/log"
+	"fmt"
 )
 
 type QRCode4BindCache struct {
@@ -16,10 +18,54 @@ const (
 	BIND_STATUS_EXPIRED = 9
 )
 
+const (
+	BIND_REPLY_SUCCESS             = "启智账号认证微信成功"
+	BIND_REPLY_WECHAT_ACCOUNT_USED = "认证失败，您的微信号已绑定其他启智账号"
+	BIND_REPLY_OPENI_ACCOUNT_USED  = "认证失败，您待认证的启智账号已绑定其他微信号"
+	BIND_REPLY_FAILED_DEFAULT      = "微信认证失败"
+)
+
+type WechatBindError struct {
+	Reply string
+}
+
+func NewWechatBindError(reply string) WechatBindError {
+	return WechatBindError{Reply: reply}
+}
+
+func (err WechatBindError) Error() string {
+	return fmt.Sprint("wechat bind error,reply=%s", err.Reply)
+}
+
 func BindWechat(userId int64, wechatOpenId string) error {
+	if !IsWechatAccountAvailable(userId, wechatOpenId) {
+		log.Error("bind wechat failed, because user use wrong wechat account to bind,userId=%d  wechatOpenId=%s", userId, wechatOpenId)
+		return NewWechatBindError(BIND_REPLY_WECHAT_ACCOUNT_USED)
+	}
+	if !IsUserAvailableForWechatBind(userId, wechatOpenId) {
+		log.Error("openI account has been used,userId=%d  wechatOpenId=%s", userId, wechatOpenId)
+		return NewWechatBindError(BIND_REPLY_OPENI_ACCOUNT_USED)
+	}
 	return models.BindWechatOpenId(userId, wechatOpenId)
 }
 
 func UnbindWechat(userId int64, oldWechatOpenId string) error {
 	return models.UnbindWechatOpenId(userId, oldWechatOpenId)
 }
+
+//IsUserAvailableForWechatBind  if user has bound wechat and the bound openId is not the given wechatOpenId,return false
+//otherwise,return true
+func IsUserAvailableForWechatBind(userId int64, wechatOpenId string) bool {
+	currentOpenId := models.GetUserWechatOpenId(userId)
+	return currentOpenId == "" || currentOpenId == wechatOpenId
+}
+
+//IsWechatAccountAvailable  if wechat account used by another account,return false
+//if wechat account not used or used by the given user,return true
+func IsWechatAccountAvailable(userId int64, wechatOpenId string) bool {
+	user := models.GetUserByWechatOpenId(wechatOpenId)
+	if user != nil && user.WechatOpenId != "" && user.ID != userId {
+		return false
+	}
+	return true
+}
diff --git a/modules/auth/wechat/event_handle.go b/modules/auth/wechat/event_handle.go
index 9e05f5e6e..c49c6d763 100644
--- a/modules/auth/wechat/event_handle.go
+++ b/modules/auth/wechat/event_handle.go
@@ -9,8 +9,6 @@ import (
 	"time"
 )
 
-const BIND_REPLY = "启智账号认证微信成功"
-
 //<xml>
 //  <ToUserName><![CDATA[toUser]]></ToUserName>
 //  <FromUserName><![CDATA[FromUser]]></FromUserName>
@@ -52,12 +50,18 @@ func HandleSubscribeEvent(we WechatEvent) string {
 	}
 	qrCache := new(QRCode4BindCache)
 	json.Unmarshal([]byte(val), qrCache)
-	//todo 已绑定微信号的如何处理？
-	//更新微信openId和流水
-	BindWechat(qrCache.UserId, we.FromUserName)
+	if qrCache.Status == BIND_STATUS_UNBIND {
+		err := BindWechat(qrCache.UserId, we.FromUserName)
+		if err != nil {
+			if err, ok := err.(WechatBindError); ok {
+				return err.Reply
+			}
+			return BIND_REPLY_FAILED_DEFAULT
+		}
+		qrCache.Status = BIND_STATUS_BOUND
+		jsonStr, _ := json.Marshal(qrCache)
+		redis_client.Setex(redis_key.WechatBindingUserIdKey(sceneStr), string(jsonStr), 60*time.Second)
+	}
 
-	qrCache.Status = BIND_STATUS_BOUND
-	jsonStr, _ := json.Marshal(qrCache)
-	redis_client.Setex(redis_key.WechatBindingUserIdKey(sceneStr), string(jsonStr), 60*time.Second)
-	return BIND_REPLY
+	return BIND_REPLY_SUCCESS
 }
diff --git a/modules/context/auth.go b/modules/context/auth.go
index 48a23e421..b374e385b 100755
--- a/modules/context/auth.go
+++ b/modules/context/auth.go
@@ -127,7 +127,7 @@ func Toggle(options *ToggleOptions) macaron.Handler {
 			}
 		}
 
-		if options.WechatAuthRequired {
+		if setting.WechatAuthSwitch && options.WechatAuthRequired {
 			if !ctx.IsSigned {
 				ctx.SetCookie("redirect_to", setting.AppSubURL+ctx.Req.URL.RequestURI(), 0, setting.AppSubURL)
 				ctx.Redirect(setting.AppSubURL + "/user/login")
diff --git a/modules/setting/setting.go b/modules/setting/setting.go
index 227a05656..06cbd6de5 100755
--- a/modules/setting/setting.go
+++ b/modules/setting/setting.go
@@ -535,6 +535,7 @@ var (
 	WechatAppId               string
 	WechatAppSecret           string
 	WechatQRCodeExpireSeconds int
+	WechatAuthSwitch          bool
 
 	//nginx proxy
 	PROXYURL string
@@ -1355,6 +1356,7 @@ func NewContext() {
 	WechatAppId = sec.Key("APP_ID").MustString("wxba77b915a305a57d")
 	WechatAppSecret = sec.Key("APP_SECRET").MustString("e48e13f315adc32749ddc7057585f198")
 	WechatQRCodeExpireSeconds = sec.Key("QR_CODE_EXPIRE_SECONDS").MustInt(120)
+	WechatAuthSwitch = sec.Key("AUTH_SWITCH").MustBool(true)
 
 	SetRadarMapConfig()