修改京东付款默认的银行卡号：可以在京东我的钱包里把原来的绑定的银行卡删除，重新绑定新的银行卡即可。具体的操作步骤如下：
（1）登录京东手机端首页。
/iknow-pic.cdn.bcebos.com/d439b6003af33a876710f4f3c85c10385243b5de"target="_blank"title="点击查看大图"class="ikqb_img_alink">/iknow-pic.cdn.bcebos.com/d439b6003af33a876710f4f3c85c10385243b5de?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/d439b6003af33a876710f4f3c85c10385243b5de"/>
（2）点击右下角我的。
/iknow-pic.cdn.bcebos.com/279759ee3d6d55fbd49782cf63224f4a21a4dd82"target="_blank"title="点击查看大图"class="ikqb_img_alink">/iknow-pic.cdn.bcebos.com/279759ee3d6d55fbd49782cf63224f4a21a4dd82?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/279759ee3d6d55fbd49782cf63224f4a21a4dd82"/>
（3）进入页面点击我的钱包。
/iknow-pic.cdn.bcebos.com/10dfa9ec8a1363273e7436da9f8fa0ec09fac7ba"target="_blank"title="点击查看大图"class="ikqb_img_alink">/iknow-pic.cdn.bcebos.com/10dfa9ec8a1363273e7436da9f8fa0ec09fac7ba?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/10dfa9ec8a1363273e7436da9f8fa0ec09fac7ba"/>
（4）点击我的银行卡。
/iknow-pic.cdn.bcebos.com/2fdda3cc7cd98d10aa54f8d82f3fb80e7aec9053"target="_blank"title="点击查看大图"class="ikqb_img_alink">/iknow-pic.cdn.bcebos.com/2fdda3cc7cd98d10aa54f8d82f3fb80e7aec9053?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/2fdda3cc7cd98d10aa54f8d82f3fb80e7aec9053"/>
（5）点击原先的银行卡。
/iknow-pic.cdn.bcebos.com/6609c93d70cf3bc76e553905df00baa1cc112a86"target="_blank"title="点击查看大图"class="ikqb_img_alink">/iknow-pic.cdn.bcebos.com/6609c93d70cf3bc76e553905df00baa1cc112a86?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/6609c93d70cf3bc76e553905df00baa1cc112a86"/>
（6）点击删除。
/iknow-pic.cdn.bcebos.com/3b87e950352ac65c8152929af5f2b21192138a80"target="_blank"title="点击查看大图"class="ikqb_img_alink">/iknow-pic.cdn.bcebos.com/3b87e950352ac65c8152929af5f2b21192138a80?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/3b87e950352ac65c8152929af5f2b21192138a80"/>
（7）回到我的银行卡页面点击增加银行卡。
/iknow-pic.cdn.bcebos.com/b7003af33a87e950bae807851e385343faf2b458"target="_blank"title="点击查看大图"class="ikqb_img_alink">/iknow-pic.cdn.bcebos.com/b7003af33a87e950bae807851e385343faf2b458?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/b7003af33a87e950bae807851e385343faf2b458"/>
（8）输入银行信息手机号点击同意协议并绑定进行绑定新的银行卡即可。
/iknow-pic.cdn.bcebos.com/d4628535e5dde7112a3cb71fa9efce1b9c166169"target="_blank"title="点击查看大图"class="ikqb_img_alink">/iknow-pic.cdn.bcebos.com/d4628535e5dde7112a3cb71fa9efce1b9c166169?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/d4628535e5dde7112a3cb71fa9efce1b9c166169"/>
这样就解决了修改京东付款默认的银行卡号的问题了。