Abstract:10 and 20g/kg ig of Rhizoma Alismatis (RA) markedly decrease the clearence rate of charcoal particles in mice, but have no significant effect on the weight of immune organs, or on the content of serum antibody hemolysin and immunoglobulin G and the delayed footpad edema induced by sheep red blood cell. The contact dermatitis of mouse pinnae immunized with dinitrochlorobenzene is inhibited by RA when it is given before challenge. In addition, RA 20g/kg suppresses the swelling of mouse pinnae induced by xylene and the proliferation of granuloma induced by cotton-pellet in rats. However, the content of vitamin C in the adrenal of rats is not clearly affected by RA.