Plant pests have been a major problem in agricultural production. To establish sustainable methods for plant pest control, 20 of plant material extracts were selected which were synergistic with Osthole to improve the performance of the osthole existing in products. The preliminary screening results indicated that Zanthoxylum bungeanum Maxim. (Z. bungeanum Maxim) compounds exerted the highest synergism. A single dose (2000 mg ? L-1) of Z. bungeanum Maxim. crude extracts was used against Plutella xyllostella (P. xyllostella), Lipaphis erysimi (L. erysimi), and Sitophilus zeamais (S. zeamais). For a further examination form Z. bungeanum Maxim., in which crude extracts were mixed with osthole at different ratios. The volume ratio of 7 : 3 (Z. bungeanum Maxim. extract: osthole) exhibited a more pronounced synergistic effect, and all the values of the co-toxicity coefficients were above 120. Eight distinct compounds were derived from the ethanol crude extract from Z. bungeanum Maxim. Then, the toxicity of these components to pests, such as P. xyllostella, L. erysimi, S. zeamais, Rhizopertha dominica (R. dominica), and Tribolium castaneum Herbst (T. castaneum Herbst), was determined. The results indicated that Compound 4 and Compound 7 exerted lethal effects on pest investigation. Compound 4 had the most substantial insecticidal action, at a concentration of 64 ug ? mL-1, and a death ratio of 78.3％ was achieved for P. xyllostella.