In the process of real commodity price movement, the basis is always changing, and the changing form of the basis is very important for a hedger. When the futures contract expires, the spot price and futures price tend to be consistent, and the basis changes seasonally. Hedgers can use the futures market to reduce the risk of price fluctuation. The change of basis is the basis for judging whether hedging can be fully realized. Hedgers can not only get better hedging effect by taking advantage of the favorable change of basis, but also get extra surplus through hedging transactions. Once the basis changes adversely, the effect of hedging will be affected and suffer certain losses. The complete hedging of futures means that futures and spot are operated in the same amount and in the opposite direction, without loss (profitability), and complete hedging is realized.