In an attempt to investigate the effect of Beekeumsan on the hemostatic action and isolated uterine muscle, Beekeumsan was administered orally and the bleeding time in mouse tail, prothrombin time in vitro were estimated. Its activity on the isolated uterine muscle in rats were investigated. The following results were obtained; The bleeding time was not shortened, but the plasma prothrombin time in vitro was significantly shortened. The uterotonic action produced by the Beekeumsan was not inhibited by pretreatment of atropine, but was slightly inhibited by cyproheptadine and completely inhibited by pretreatment of diltiazem.