The invention discloses a method for preventing and treating tobacco common mosaic, and belongs to the technical field of tobacco planting. The cured tobaccos infected before binding in each mu of tobacco fields are sprayed once every 7 days and 3-5 times continuously with a mixture containing 30L of a salix myrtillacea extract solution prepared according to the method provided by the invention, 4-8g of brassinolide, 1-2g of ningnanmycin, 200-400g of urea, and 20-60g of zinc sulfate, which are mixed and dissolved together; and the cured tobaccos infected after binding in each mu of tobacco fields are sprayed once every 7 days and 3-5 times continuously with a mixture containing 30L of the salix myrtillacea extract solution prepared according to the method provided by the invention, 4-8g of the brassinolide, 1-2g of the ningnanmycin, and 20-60g of zinc sulfate, which are mixed and dissolved together, and the use of the mixture is stopped 3-5 days before harvest if the tobaccos enter a harvest period. According to the method, the tobacco common mosaic can be effectively prevented and treated, and compared with a chemical method for prevention and treatment, the method is low in cost, low in residue and difficult in generation of drug resistance for diseases and insect pests, and can protect natural enemies of the tobacco diseases and insect pests.