If it is a debit card, there is no limit. One person can open a lot of cards. The only thing to note is that an ID card can only open an online bank, which means that if you have several ordinary banks of China Merchants Bank. Cards (China Merchants Bank called China Merchants Bank) can only choose one of them to open online banking, and then link the other ones to the online banking. ifcredit card
If there is a restriction, China Merchants Bank can open up to three credit cards under the name of an ID card.