The soybean aphid,Aphis glycines Matsumura(Hemiptera: Aphididae),is a significant pest in soybean-growing regions.This study evaluated the functional and numerical responses of three species of predators,Harmonia axyridis(Pallas)(Coleoptera: coccinellidae),Propylaea japonica(Thunberg)(Coleoptera: coccinellidae),and Chrysoperla sinica Tjeder(Neuroptera: Chrysopidae)with A.glycines as the host,under laboratory conditions.The results showed that H.axyridis and P.japonica were highly effective while C.sinica was the moderately effective in feeding on A.glycines.Logistic regression analysis suggested Type II(convex)functional responses for all three species.However,based on the estimates of the handling time and the attacking rates,the three predators had different predation capacities.Among the three species,H.axyridis had the highest predation on A.glycines.The maximum daily predation by a female H.axyridis was 3560.74 aphids/day,followed by a forth instar larval H.axyridis(904.90 aphids/day),a female P.japonica(500.00 aphids/day),a forth instar larval P.japonica(504.13 aphids/day)as well as a third instar larval C.sinica(240.48 aphids/day).For H.axyridis and P.japonica,the attack rate was highest for adult females,followed by fourth instar larvae and adult males.For C.sinica the attack rate was highest for third instar larvae,followed by second and first instar larvae.The findings from this study could help select better biological control agents for effective control of A.glycines.