Four related randomized and controlled experiments were performed to evaluate the effects of Epimedium-Propolis adjuvant (EPA) on T lymphocyte transformation rates in mice and chicks and antibody levels in rabbits and chickens. In Experiment I, mice were divided into 4 groups and injected with the immunosuppressive agent cyclophosphamide (Cy), or EPA+Cy, or EPA only and compared to untreated saline control. Results showed that Cy down-regulated T lymphocyte transformation rate (SI), while EPA up-regulated it. In Experiment II, chicks were injected with either 0.2 ml or 0.4ml EPA and compared to untreated saline control. EPA increased SI in a dose dependent and age related manner in chicks. In experiment III, infectious canine hepatitis virus (ICHV) antibody level was evaluated in rabbits injected with virus + EPA and without EPA. Antibody levels were higher in the EPA group. Experiment IV results demonstrated that EPA and Freund’s adjuvant (FA) created nearly equal antibody increases in hens, however, EPA did not demonstrate the adverse side effects seen with FA. In conclusion, EPA improved cellular and humoral immune function of animals in a dose dependent manner with the greatest intensity of the effect in young animals. In addition, the use of EPA as an adjuvant is as effective as Freund’s adjuvant but without the deleterious side effects on health. This study adds to the body of research demonstrating the benefit of using the Chinese herbal medicine, Epimedium along with extracts from propolis as an adjuvant in vaccines for animals.