OBJECTIVE： To study the preventive and therapeutic effect and its mechanism of medicine pair decoction liquid of Curcuma phaeocaulis-Sparganium stoloniferum on rats with uterine myoma. METHODS： Rats were randomly divided into normal group， model group， positive group （mifepristone，2.25 mg/kg） and medicine pair decoction liquid group （C. phaeocaulis-S. stoloniferum decoction liquid， 6.0 g/kg）， 10 in each group. Except for the normal group， rats in other groups were injected Estradiol benzoate injection （0.5 mg/kg） intramuscularly every Monday， Wednesday and Friday， for 12 weeks. From the 13th week， rats in modeling group were added Progesterone injection （5 mg/kg） intramuscularly as well as relevant medicines intragastrically， once a day， until the 16th week. After administration， uterine coefficient of rats was detected. HE staining was used to observe the pathological changes of uterus and determine the thickness of smooth muscle； immunohistochemical staining was adopted to detect the transforming growth factor β3 （TGF-β3）， matrix metalloproteinase 11 （MMP-11） protein expressions in uterus tissue of rats. RESULTS： Compared with normal group， uterine coefficient was increased in model group， pathological changes were obvious in uterus， thickness of smooth muscle was increased， TGF-β3 and MMP-11 protein expressions were enhanced （P＜0.05 or P＜0.01）. Compared with model group， above-mentioned changes were improved significantly in positive group and medicine pair decoction liquid groups （P＜0.05 or P＜0.01）. CONCLUSIONS： Medicine pair decoction liquid of C. phaeocaulis-S. stoloniferum shows certain preventive and therapeutic effect on rats with uterine myoma. The mechanism may be associated with downregulating the TGF-β3， MMP-11 protein expressions in uterus tissue.