Objective To explore the clinical value of transvaginal three-dimensional color Doppler ultrasound in assessing effects of Chinese herbal drugs on improving endometrial receptivity in patients with thin endometrium.Methods A total of 76 cases of patients diagnosed with thin endometrium in Jiangbei District Hospital of Traditional Chinese Medicine from June 2015 to October 2016 were selected and treated with Chinese herbal prescription for three months.The endometrial thickness,endometrial volume and blood flow indexes before and after treatment were measured by using transvaginal three-dimensional color Doppler ultrasound.Results After 3 months treatment,the endometrial thickness and endometrial volume were increased,and the pulse index (PI) and resistance index (RI) of endometrial blood flow were decreased,compared with those before treatment,there were statistically significant differences(P＜0.05).The results of three-dimensional color Doppler ultrasound indicates that after 3 months treatment the vascularization index (VI),flow index (FI) and vascularization flow index (VFI) were significantly higher than those before treatment,there were statistically significant differences (P＜0.05).Conclusion The Chinese herbal prescription could increase the thickness and volume of endometrium,augment blood supply,and improve endometrial receptivity significantly.Transvaginal color three-dimensional Doppler ultrasound is a convenient and objective method for evaluating clinical efficacy of Chinese herbal prescription in patients with thin endometrium,which has high practical value.