BACGROUND: To examine effect of omahwan(烏麻丸)-赤何首烏(Polygonum multiflorum THUNB.), 白何首烏(Cynanchum wilfordii H.), 黑芝流(Sesamum indicum L.)-on the aged human immune system a series of humoral immunological parameters was compared in aged female (age 60-70 years) before and after administration of omahwan(烏麻丸). METHODS: Peripheral blood was obtained from fifteen healthy young (age 20-29, mean=66.3) female volunteers. B cell, T cell(T cells, T helper, and T suppressor/ cytotoxic) subsets was examined with specific monoclonal antibodies and isotype controls, using dural color flow cytometer IL-2 was examined with ELISA kit RESULT: By comparing the immune characteristics of the younger and elder groups the total ratio of T-cell, CD8 T-cell and quantify of IL-2 was significantly lower while CD4/CDB ratio was considerably greater in the elder group. ( p(0.05, student t-test) After giving Omahwan for 30 days to the elder group, by comparing the ratio before and after Prescription the total T cell and CD8 T cell ratio was considerably greater after prescription (p(0.05, Paired t-test) The quantity of IL-2 tended to increase after prescription but has no statistical meaning. CONCLUSION: The results indicate that administration of Omahwan(烏麻丸) differentially affects various aspects of the immune system in aged human.