The effects of orally administered ginseng leaf saponins(GLS) on the analgesic action of morphine, the development of morphine induced tolerance and physical dependence, and the hepatic flutathione contents in mice were investigated. GLS antagonized the analgesic action of morphine and inhibited the development of morphine induced tolerance and physical dependence. It also inhibited the decrease in hepatic glutathione level induced by multiple injections of morphine. Keywords H Panax ginseng C.A. Meyer, morphine. glutathione, ginseng leaf saponin