The objective of this study was to investigate VA5 immunopotentiator efficacy on the trivalent oil emulsion vaccine and the productivity of broiler chickens. The antibody titer, production of cytokines and productivity was evaluated after the VA5 mixing with the commercial trivalent vaccine, Newcastle disease(ND)-Infectious Bronchitis(IB)-H9 Subtype Avian Influenza(AI(H9)) vaccinated in Chinese color-feathered broiler chickens. In the vaccination groups of trivalent vaccine with VA5, the hemagglutination inhibition(HI) antibody titers of sera or bronchoalveolar lavage fluids(BAL) against NDV, IBV and H9 AIV were significant higher than those in groups received trivalent vaccine without VA5 post vaccination(pv), respectively. Similar to the HI antibody levels, the IgA antibody levels in tears or small intestine mucus against NDV, IBV and AIV(H9) were higher in groups of trivalent vaccine with VA5 than those of the trivalent vaccine only. The expression of interferon(IFN)-gamma, interleukin(IL)-4 in sera also enhanced by VA5 immunopotentiator. In addition, our data showed enhanced the qualified rate of HI antibody, average survival rate of broilers, weight, synthetic economy benefit and depressed feed conversion ratio, respiratory morbidity, mortality and elimination rate after administration trivalent vaccine with VA5 as compared to those of chickens inoculated with the trivalent vaccine alone. In conclusion, the study demonstrated the compound preparation of VA5 immunopotentiator is helpful on improving the efficacy of trivalent vaccine or the productivity in broiler chickens and shows prosperity in application.