The invention provides a large-scale breeding and afforestation method for Chinese chestnuts, and relates to the technical field of forest cultivation. The breeding and afforestation method comprises the four stages of seed treatment, seedling raising, transplanting and young forest management for large-scale breeding and afforestation. According to the breeding and afforestation method, planting seeds with the high survival rate are obtained by selecting the seeds and conducting sand storage with the plant ash, the coarse sand and the fine sand, planting is conducted after disinfection and germination acceleration are conducted, seedlings are cultivated, and at the moment, the growth condition of the seedlings is good. The cultivated seedlings are transplanted to a land parcel with the relative humidity of 25%-30%, the plant spacing is 2 m * 2 m, and it is avoided that the chestnut trees shield each other in the growth process, and the photosynthesis of the chestnut trees is affected. After the seedlings grow in the adaptive period, regular watering, fertilization, impurity removal, soil loosening and pest management are conducted on the seedlings, so that the seedlings grow healthily to be adult, and then the effect of increasing the yield is achieved.