The invention discloses a method for reducing burley tobacco nicotine, which comprises the following steps: selecting a tomato seedling as a stock and a burley tobacco seedling as a cion, grafting by adopting a cleft graft method, horizontally cutting off the upper half part of the stock that is 8 cm to 10 cm from the soil surface, and vertically downwards cutting a cut with the length of 1 cm; cutting off the upper half part of the cion from a parent, grinding two sides of a stem into wedge-shaped structures with the length of 1 cm, vertically inserting the wedge-shaped structure into the stock, fixing by a grafting clip, and moving into a coalescence curing chamber. The synthesis of the burley tobacco rooted nicotine is controlled manually through a grafting manner, the burley tobacco nicotine is reduced remarkably, and the problem that the content of the burley tobacco nicotine is too high is solved effectively. As burley tobacco and tomatoes are classified as solanaceae, the burley tobacco and the tomato have good affinities, and the grafting success rate reaches more than 70%. The content of nicotine of the burley tobacco and tomato combination is reduced remarkably, the field growth condition is basically consistent with the cion own-rooted seedling, and the acre yield remains almost the same.