只要QQ号绑定了微信，就可以用QQ号来登录微信。下面以苹果6sp微信6.3.25版为例，用QQ号登录微信的步骤如下：
1：打开微信登录页面，点击最下面的“更多”
/iknow-pic.cdn.bcebos.com/4610b912c8fcc3ceb5acb0ad9a45d688d43f203b"target="_blank"title="点击查看大图"class="ikqb_img_alink">/iknow-pic.cdn.bcebos.com/4610b912c8fcc3ceb5acb0ad9a45d688d43f203b?x-bce-process=image%2Fresize%2Cm_lfit%2Cw_600%2Ch_800%2Climit_1%2Fquality%2Cq_85%2Fformat%2Cf_auto"esrc="
https://iknow-pic.cdn.bcebos.com/4610b912c8fcc3ceb5acb0ad9a45d688d43f203b"/>
2：再点击“切换账号”
/iknow-pic.cdn.bcebos.com/fd039245d688d43ffcebe86c751ed21b0ff43be9"target="_blank"title="点击查看大图"class="ikqb_img_alink">/iknow-pic.cdn.bcebos.com/fd039245d688d43ffcebe86c751ed21b0ff43be9?x-bce-process=image%2Fresize%2Cm_lfit%2Cw_600%2Ch_800%2Climit_1%2Fquality%2Cq_85%2Fformat%2Cf_auto"esrc="
https://iknow-pic.cdn.bcebos.com/fd039245d688d43ffcebe86c751ed21b0ff43be9"/>
3：然后如下图所示点击“微信号/邮箱地址/QQ号”
/iknow-pic.cdn.bcebos.com/8cb1cb134954092390af1ae09a58d109b2de496d"target="_blank"title="点击查看大图"class="ikqb_img_alink">/iknow-pic.cdn.bcebos.com/8cb1cb134954092390af1ae09a58d109b2de496d?x-bce-process=image%2Fresize%2Cm_lfit%2Cw_600%2Ch_800%2Climit_1%2Fquality%2Cq_85%2Fformat%2Cf_auto"esrc="
https://iknow-pic.cdn.bcebos.com/8cb1cb134954092390af1ae09a58d109b2de496d"/>
4：然后输入QQ号和密码就可以登录微信了
/iknow-pic.cdn.bcebos.com/00e93901213fb80e52ff19493ed12f2eb9389405"target="_blank"title="点击查看大图"class="ikqb_img_alink">/iknow-pic.cdn.bcebos.com/00e93901213fb80e52ff19493ed12f2eb9389405?x-bce-process=image%2Fresize%2Cm_lfit%2Cw_600%2Ch_800%2Climit_1%2Fquality%2Cq_85%2Fformat%2Cf_auto"esrc="
https://iknow-pic.cdn.bcebos.com/00e93901213fb80e52ff19493ed12f2eb9389405"/>