Abstract: Nicotiana glutinosa and N. tabacum var. Samsun (NN) were inoculated with TMV solution in five different concentrations, respectively. Then the shape, number and size of local necrotic lesions in different treatments were recorded and analyzed. The results showed that the shape of local necrotic lesions formed in two tobacco varieties had no difference, and there was significant difference between average number of local necrotic lesions on the leaf of N. glutinosa and virus concentration (r=0.958， p<0.05). There were more small local necrotic lesions and less large local necrotic lesions on the leaf of N. Tabacum var. Samsun (NN) than that of N. glutinosa, and the difference was very significant (p<0.01).