Abstract: With the expansion of the planting area of chili peppers and watermelons, some factors restricting industrial development have also emerged in the main production areas, such as serious diseases caused by continuous cropping.The use of watermelon and chili intercropping can effectively improve the multiple cropping index and economic benefits, and reduce the occurrence of diseases.During the hot season, the leaves and vines of watermelons block out strong light, which can lower the soil surface temperature by more than 5 ℃,reduce the harm of high temperature and strong light to chili peppers, reduce disease and yield, and create conditions for high yield.At the same time, the pepper plant partially blocks the light of the watermelon, reducing the exposure of strong light to the sun, which is beneficial for the growth of the watermelon.This technology aimed to promote the development of the agricultural industry, increased agricultural efficiency, and increase farmers′ income.It played an important role and significance in accelerating the structural adjustment of the agricultural planting industry in Inner Mongolia region, promoting the development of new modern agriculture, and promoting the long-term, healthy, and efficient development of the agricultural industry in Inner Mongolia region.