A prospective clinical trial was carried out to explore the hemostatic effect of Gongxueting Mixture on metrorrhagia and metrostaxis with blood stasis syndrome and its mechanism. Bleeding time and bleeding volume in 37 cases were detected before and after treatment to assay the hemostatic effect. Indexes of blood analysis, blood rheology, blood coagulation and prostaglandin in 8 cases were determined to study the mechanism. The results showed that Gongxueting Mixture shortened the menstrual period and regulated the volume of menses (P 0.05 ). It is concluded that Gongxueting Mixture is effective for metrorrhagia and metrostaxis with blood stasis syndrome (the total effective rate being 91.89% ), and enhancement of platelet aggregation, promotion of fibrinolytic activity and regulation of prostaglandin release may be its hemostatic mechanism.