This study was done to know the effects of the water extracts of Gyogamdan(GGD) on the function of macrophages, the most important cells of the innate immune system, and the rosette forming ability of splenocytes in the mouse under stress. The effects of GGD on the immunosuppression induced by noise stress are as follows. 1. Administration of GGD water extracts normalized the bo요 weight which might be decreased by noise stress. 2. Administration of GGD water extracts increased the production of the such reactive oxygen intermediates as superoxide and hydrogen peroxide from macrophsges in vivo & in vitro which were decreased by noise stress. 3. Administration of GGS water extracts did not affect the production of reactive nitrogen intermediates. 4. Administration of GGD water extracts increased the rosette forming ability of splenocytes which was decreased by noise stress. The above effects of GGD might be useful for the treatment of stress-induced infections diseases which could be caused by the suppression of immune responeses which are initiated by the functions of macrophages of the innate immune system.