Sudden vaginal bleeding after three years of menopause can be seen in many kinds of diseases, such as cervical neoplastic lesions, endometrial tumors, ovarian tumors, cervical inflammation, uterine inflammation, polypoid proliferation and so on. If patients take some health care products for a long time, especially those containing estrogen components, they can also experience abnormal proliferation of the endometrium and vaginal bleeding. Therefore, if a patient suddenly develops vaginal bleeding after three years of menopause, it is necessary to collect some information first and find out the cause in order to treat the symptoms. Firstly, gynecological internal examination is needed to observe whether there are any lesions in the vagina and cervix, and cervical screening is also needed. Secondly, a gynecological ultrasound is needed to observe if the uterus is atrophied, the thickness of the endometrium and the condition of the ovaries. If there are problems with these tests, further hysteroscopy, colposcopy, tumor markers, CT, MRI and a series of other tests are needed.