Postmenopausal endometrial thickness is a double layer not exceeding 4mm. Endometrial thickening in postmenopausal women is usually no more than 4mm, and cunnilingus is generally used as the preferred modality for its examination. Postmenopausal endometrial thickening can be seen in conditions such as endometrial cancer, endometrial polyps, and submucosal fibroids. For postmenopausal women with bleeding, ultrasound is needed to check for endometrial thickening and further diagnostic curettage is needed to confirm the diagnosis. It is recommended that postmenopausal women should have regular checkups, and if endometrial thickness of 4mm is found during physical examination, they should consult the gynecology outpatient clinic in time, and the professional doctor should decide the next diagnostic and treatment measures according to the patient’s clinical manifestations and high-risk factors, so as to avoid delaying the time of diagnosis and treatment.