People's currency exchange can be divided into three levels: non-convertible, convertible under current account of balance of payments and fully convertible, that is, freely convertible under current account and capital account. With the continuous development of China's financial market, the rapid growth of international trade and investment scale, China's accession to the World Trade Organization and the strengthening of regional economic cooperation, it is objectively required that RMB be convertible under capital account as soon as possible, but the International Monetary Fund has not given a strict definition of convertibility under capital account.