Abstract: The structure and development regularity of floral organs and receptive period of female flowers were studied for Carya cathayensis by means of emasculation,bagging and controlled pollination techniques.The results showed that there was an eminent adaptive mechanism for anemophilous pollination in the floral organs of C.cathayensis.The pollinating period of male flower was short,which concentrated in only 3d and exhibited eruptive phenomenon.The color of female flower stigma changed successively in the order of turquois,reddish,cerise,purplish red and atropurpureus during flowering stage,and the development process of female flowers was different.The optimal receptive stage for C.cathayensis female flowers was when the stigma color exhibited cerise,by which the fruit setting percentage could reach 47.77%.The receptive period of female flowers was about 10d waiting for pollination.