Abstract: The present paper reports the effects of Saussurea Polysaccharide (SPS) on the isolated rat uterus. SPS showed stimulating effects on the isolated rat uterus at every stage of sexual cycle. After administration of SPS, the amplitude, frequency and tonus of the uterus contraction were increased immediately and significantly. The effects were more obvious on oestrous uteri. The potency and duration of action of SPS were dose-dependent. The stimulating effects of SPS on uteri were potentiated by PGE₂ and decreased by indomethacin. It is possible that the mechanisms of SPS action may be due to its direct effect on the uterine smooth muscle or its promotive effect on PGs synthesis in the uteri.