To evaluate the risk of clipping-leaves to transmiting tobacco bushy top disease in floating system, tobacco seedling were clipped using scissors clipped the leaves with tobacco bushy top virus(TBTV) and tobacco mosaic virus(TMV)and dipped the two virus solution, respectively. The incidence of TBTV and TMV were investigated after 28 days, the data indicated that the two clipping treatment methods in floating system can not transmitted TBTV, but the average incidence of TMV were 36.67% and 63.33%, respectively. The results suggested that clipping treatment in floating system is not easy to transmit TBTV, but is easy to transmit TMV.