To investigate the possibility of Panax ginseng as a therapeutic agent for the immune suppression, ginseng total saponin (GTS) extracted from korean red ginseng was tested on immune functions from morphine-induced immune suppressed mice. To study how immune functions are affected by morphine and also to test whether GTS can be an useful therapeutic agent for morphine toxicity, several parameters were employed, body weight, immune organ weight, B cell functions, and T cell function. Morphine impaired the development of body weight and immune organ weight such as spleen and thymus. Morphine also depressed a B-cell function, antibody production. T-cell functions studied by type IV hypersensitivity test were most markedly affected by morphine treatment. GTS restored most of morphine-induced immune suppression. GTS restored the morphine-induced decrease in spleen weight to body weight ratio in a dose dependent manner, but not the body weight decrease. Also all of the morphine-induced impairments of B cell functions and cellmediated immunity were fully recovered by GTS. These results suggest that ginseng product could be very helpful for the treatment of immune suppression occurring in morphine abusers.