The settlement of stock index futures can be roughly divided into two levels: first, the clearing house or the settlement department of the exchange settles the members, and then the members settle the investors. No matter what level it is, it is necessary to do three things: transaction processing and position management, financial management and risk management. (1), transaction processing and position management, that is, after trading every day, what transactions are made and what positions are held. (2) Financial management, that is, the profit and loss of the position are settled every day, and the margin is returned for the profit part and recovered for the loss part. (3), risk management, risk assessment of the settlement object, calculate the deposit. In the second part of the work, it is necessary to clarify the benchmark price of settlement, that is, the so-called settlement price, which generally refers to the average price of futures contracts in a period of time close to the closing price of the day (some directly use the closing price as the settlement price). The profit and loss of a position contract is calculated by comparing its holding cost price with the settlement price. The closing contract uses the closing price to compare with the holding cost price to calculate the profit and loss. For contracts opened on the same day, the holding cost price is equal to the opening price, and for historical contracts opened before that day, the holding cost price is equal to the settlement price of the previous day. Because the book profit and loss have been settled to investors every day, the cost price of the position contract after settlement on that day becomes the settlement price on that day. Therefore, unlike the calculation of stock cost price, the position cost price of stock index futures changes every day. With the clearing house, legally speaking, stock index futures are not directly conducted by buyers and sellers, but become the central counterparty by the clearing house, that is, the sole seller of all buyers and the sole buyer of all sellers. The clearing house uses its own assets to guarantee transactions.