Monetary fund is an open-end fund that collects idle social funds, is operated by fund managers and kept by fund custodians. It specializes in investing in low-risk money market instruments, which is different from other types of open-end funds. It has the characteristics of high security, high liquidity, stable income and "quasi-savings".

Due to the emergence of digital currency, a new type of money fund-virtual money fund has appeared in the field of money fund. Also known as the digital currency Fund.