Endometrial receptivity is the embodiment of endometrial receptivity to embryos, which is one of the key factors affecting pregnancy. Ultrasound provides a simple, economic, repeatable and noninvasive method for the evaluation of endometrial receptivity. By dynamically monitoring the changes of endometrial blood flow, peristaltic wave, volume, thickness, type, echo value, etc., ultrasound can help doctors evaluate endometrial receptivity and guide clinical practice, so as to improve the clinical pregnancy rate.