Abstract:The inhibitory action on isolated uterus of mlddle-pregnancy mice have been compared in Eucommia ulmoides and its salt water processed product. It has been found that after processing the inhibitory action on the automatic contraction of isolated uterus, the antagonism on spasmodis contraction caused by acetylcholine are increased, but the antagonism on spasmodis contraction caused by pituitarinm posterius and the Pb content are decreased.