Objective To study clinical value of transvaginal ultrasound for evaluating endometrial receptivity in infertility patients.Methods All patients were taken color Doppler flow imaging(CDFI)by transvaginal ultrasound.The data of uterus and ovarial morphous,size,endometrial thickness,the resistant index(RI)and pulsatility(PI)of uterine artery were measured and recorded.Blood flow distribution patterns in endometrium was observed by CDFI.Results The results showed 26 menstrual cycles including 8 biochemistry pregnancy circles and 20 clinical pregnancy cycles in 60 cases.The clinical pregnancy rate was 15.63%.The differences of average ages,infertility time and endometrial thickness were no significant(P0.05)between pregnancy group and non-pregnancy group.The difference of blood flow index and PDI typing of blood flow in endometrium and subendometrium was significant(P0.05).Conclusion The data of endometrial thickness and the blood flow distribution patterns in endometrium and subendometrium by transvaginal ultrasonography may help to evaluate endometrial receptivity and raise pregnaney rate in infertilities that it is guidance meanings.