The official currency is the Chinese Yuan (CNY or RMB). While credit cards (Visa/Mastercard) are accepted in major hotels, malls, and international chains, cash and mobile payments (WeChat Pay/Alipay) dominate daily life. Foreigners often found it difficult to set up Alipay/WeChat Pay without a local bank account, it is getting much easier to apply Alipay and Wechat Pay right now. When you get to the airports or railway stations, you can find posters suggesting the way to open Alipay or Wechat Pay account.
Example:
In a small noodle shop in Chengdu, the vendor may only accept WeChat Pay or cash. Having RMB notes on hand (e.g., 100 or 50 RMB bills) ensures you’re not left without options.