Abstract: The effects of several plant pesticides on tobacco diseases and pests were studied in field during 2002-2004.The results indicated that Veratrum nigrum L., Macleaya cordata (Willd.) R. Br., and Sophora flavescans Ait.had strong killing effect on Myzus persicae (Sulzer);Celastrus angulatus Maxim and Macleaya cordata (Willd.) R.Br.had obvious control effect on Helicoverpa assulta;Veratrum nigrum L., Macleaya cordata (Willd.) R.Br., Sophora flavescans Ait.and Artemisia argyi Leveille all showed control effect on Alternaria alternata, and the applying effects of Sophora flavescans Ait.and the compounds of these 4 pesticides were better;Phytolacca acinsa Roxb. had strong restraining effect on TMV.