In order to have a better exploitation and utilization for Phytolacca americana and Ginkgo biloba sarcotesta,the insecticidal activity of the extract of Phytolacca americana leaf (Pal) and Ginkgo biloba sarcotesta (Gbs) and their mixture against Plutella xylostella were tested and compared in the present paper.Results showed that,both of the two kinds plant extracts showed good insecticidal activities against Plutella xylostella,and the activity raised with the increasing of treating time and extract concentration.The extract of Gbs performed better than that of Pal at all concentrations,and the corrected mortality were 74.7% (Gbs) and 64.8% (Pal) after 72 hours treatment with 8 mg/mL concentration.The virulence regression equation were y=1.584x-1.243(Gbs) and y=1.337x-0.629(Pal) while the LC₅₀ were 2.95 mg/mL(Gbs) and 6.09 mg/mL(Pal).The insecticidal activity of the two extracts’ mixture varied with the mixing ratio and the optimum ratio was 1∶11 (Pal∶Gbs).The mixture’s LC₅₀ was 1.34 mg/mL which was lower than that of both single extract while the virulence index was 491.13 mg/mL which was higher than the sum of two single extracts’ virulence index.The co-toxicity coefficient value of 152.92 suggested a significant synergistic effect existed in mixing treatment.These results could provide some references for the new bio-pesticides exploitation based on the extract of Pal and Gbs.