The mystery of closed-end fund discount is a frontier topic in behavioral finance research, and there is no perfect explanation to convince all parties at present. Agency cost, potential tax burden, insufficient liquidity of fund assets, investor sentiment and many other factors, such as untimely publication of fund net value, lack of strong competitive cost, fixed fund scale, too few investment targets, too long investment limit and so on. 1. The net value of the base set is generally published once a week, which is not timely compared with the daily publication of the base set. 2. There is no performance pressure for fund managers who can choose, because there is no fee income, fixed management fee income and no marketing value. There are too few investable funds in the market, only a few new ones have been opened. The fundraising procedures are complicated, the institutions are single, and the investors are mostly insurance funds. This kind of capital is rational and must be discounted to be attractive. 4. If the discount rate of investors' sentiment is low when the stock market is high, but just high when it is in the bear market, it is generally around 10% abroad and around 10%-40% at home, which is directly related to the maturity date. Some foundations choose a large proportion of dividends before maturity, while others will discount them.