The provisions of margin ratio for commodity futures trading in domestic exchanges in China have the following characteristics: First, different margin ratios are stipulated for different stages of listing and operation of futures contracts. Generally speaking, the closer to the delivery month, the greater the possibility that traders will face due delivery. In order to prevent the possible default risk of physical delivery, traders who are unwilling to make physical delivery are urged to close their positions as soon as possible, and the proportion of trading margin will increase as the delivery approaches. Second, with the increase of contract positions, the exchange will gradually increase the margin ratio of this contract transaction. Generally speaking, with the increase of contract positions, especially when the number of futures commodities represented by positions contracts far exceeds the spot number of related commodities, it often indicates that there are too many speculative transactions in the futures market, which implies greater risks. Therefore, with the increase of contract positions, the exchange will gradually increase the trading margin ratio of the contract to control market risks. Third, when a futures contract continues to rise and fall, the trading margin ratio will increase accordingly. Fourth, when the price of a product contract changes according to the settlement price within one month, and the cumulative fluctuation of several consecutive trading days reaches a certain level, the trading ownership will unilaterally or bilaterally increase the trading margin for some or all members in the same proportion or in different proportions, restrict some or all members from withdrawing funds, suspend some or all members from opening new positions, adjust the range of price limit, close positions within a time limit, and forcibly close positions according to market conditions to control risks. Fifth, when there is abnormal trading in futures contracts, the exchange can adjust the trading margin ratio according to the prescribed procedures. In China, the margin paid by futures traders can be funds or securities with stable value and strong liquidity, such as standard warehouse receipts or treasury bonds.