Abstract: In this paper,processing method of pouring and spraying were respectively used.The control agent on Sclerotium rolfsii Sacc.of pouring and spraying were screened,and the optimum control period had been studied. The results showed that the best result of control agent of pouring was"enhao"f 1000 times dilution,and the was 2.8%,the control efficacy was 89.8%;The best result of of spraying was"ymevazol"1500 times,the average incidence was 5.6%,the control efficacy was 80.1%;and optimum prevent time was 2.5 inch cup seedlings for five days before changing the cup.