[ Objective ] The paper was to explore the application of botanical pesticides on controlling turnip aphid ( Lipaphis erysimi Kaltenbach). [ Method ] Through potting efficacy experiment of Chinese cabbage, the control effects of two preparations(20% EC and 10% EW)of methanol extract of Blumea megacephala Chang et Tseng against turnip aphid, as well as leaf-protection effect on Chinese cabbage were determined. [ Result] 20% EC of B. megacephala had the highest efficacy in 10-fold dilution, and its control effects against turnip aphid were 57.78%, 77.19% and 84.79% after pesticide spraying for 24, 48 and 72 h; 10% EW of B. megacephala had the highest efficacy in 5-fold dilution, and its control effects against turnip aphid were 74.44%, 84.79% and 89.14% after pesticide spra- ying for 24, 48 and 72 h. The leaf-protection rates of 20% EC orB. megacephala in 10-fold dilution were 89.31% and 94.80% after pesticide spraying for 3 and 5 d; the leaf-protection rates of 10% EW of B. megacephala in 5-fold dilution were 93.50% and 97.83% after pesticide spraying for 3 and 5 d. [ Condusion] The methanol extract of B. megacephala had good control effect against turnip aphid and good protection rate on crops.