Abstract: The Phellodendron chinense bark and leaf extracts were used as the control agent for Bletilla striata rust disease. The incidence rate, disease index, control effect and disease grade distribution of Bletilla striata rust disease under the treatment of the control agent were counted, and the control effect of Phellodendron chinense extract on Bletilla striata rust disease was discussed, and the prevention and control mechanism of Phellodendron chinense extract on Bletilla striata rust disease was clarified. The results showed that the incidence rate and disease index of Bletilla striata rust disease were the lowest under ZP50 treatment. In June, the disease index was Y50>CK>Y25>P25>ZP25>P50>ZP50. Compared with CK, ZP50 treatment had the best control effect, and the control effect was 93.64% in July. From the distribution of disease levels in June and July, the disease severity of Bletilla striata was weak under ZP50 treatment. The ZP50 treatment could control the critical degree of Bletilla striata rust and reduce the disease index by reducing the incidence of Bletilla striata rust and regulating the proportion of disease conditions of grade 1, 7 and 9. Overall, the control effect of Phellodendron chinense bark extract was better than that of Phellodendron chinense leaf extract, and the control effect of boiled Phellodendron chinense bark extract was better than that of uncooked Phellodendron chinense bark extract, and high concentration Phellodendron chinense bark extract had better control effect than low concentration Phellodendron chinense bark extract. Phellodendron chinense extract can be used as a green control agent for Bletilla striata rust disease.