Abstract: The method of determining tobacco loss caused by pests was studied in laboratory and tobacco storehouse by introducing tobacco beetles and having the tobacco damaged to different degrees.The results showed that there was an extremely significant positive correlation between the mass loss rate of strips and the rate of dust and insect carcass, the mass lose rate of strips could be estimated by the rate of dust and insect carcass in the stored tobacco.The losses of strips damaged by pests in several domestic cigarette enterprises were investigated with the method, the direct loss rate of 46 strip samples was about 0.716%;given the infected tobacco accounted for 30%of the total stored tobacco, the estimated direct loss rate in investigated cigarette enterprises was about 0.215%.