Fund index is an index standard based on the data of securities investment funds listed on the stock exchange. Among them, the securities investment fund refers to an investment tool that raises funds by selling fund shares, and then the fund share holders enjoy the benefits and bear the risks according to their holdings. Fund index is generally calculated according to the data in the reporting period, and its calculation formula is: fund index in the reporting period = (total market value of funds in the reporting period ÷ total market value of funds in the base period) × base period index.

As a quantitative index of fund trading market, fund index can reflect the price trend of a fund for fund investors, thus helping fund investors to understand the basic situation of the fund.