[Immunomodulatory effects of a mixture of Apostichopus japonicus and Cordyceps militaris on immunocompromised mice]. OBJECTIVE:  To evaluate the immunomodulatory effect of a mixture of A. japonicus and C. militaris on immune functions of immunocompromized mouse model. METHODS:  Fifty Balb/c mice were randomly selected and assigned into five groups (ten animals per group): a normal control group, a model control group, a positive control group and low and high dose groups. A mixture of A. japonicus and Cordyceps militaris was administered orally every day to mice in dose groups at a dosage of 60 and 120 mg/kg x bw respectively. Mice in positive control group were given orally with levamisole hydrochloride at a dosage of 20 mg/kg x bw. Mice in normal and model control groups were administered with 0.9% NaCl solution as placebo. All agents were administered once a day for 28 days. On the 21st day, all mice except that in the normal group were injected hypodermally with hydrocortisone at a dosage of 22.5 mg/kg x bw once a day for 7 days to generate a immunocompromised animal model. The mice were deprived of food for 12h after the last administration, and the delayed type hypersensitivity (DTH), hemolysin, antibody forming cells, the clearance of carbon particles in macrophages, the production of cytokine IFN-gamma and IL-4 were measured respectively. RESULTS:  The DTH level (P < 0.01), hemolysin content (P < 0.01) and the number of antibody forming cells (P < 0.05), carbon particle clearance index (P < 0.01) in immunocompromised mice administered with the mixture of A. japonicus and C. militaris were increased obviously. At the same time, the mixture could also enhance IFN-gamma (P < 0.01) content and reduce IL-4 (P < 0.05) content. CONCLUSION:  Both the specific and non-specific immune function in immunocompromised mice could be stimulated by the mixture of A. japonicus and C. militaris.