Endometrial atypical hyperplasia is a manifestation of endometrial hyperplasia and is a precancerous endometrial lesion. It has been found that if left untreated, 20% to 52% can develop into endometrial cancer. Clinical symptoms include: (1) abnormal menstruation, which can be manifested as irregular vaginal bleeding, sporadic menstruation or prolonged heavy vaginal bleeding after amenorrhea; (2) anemia, which is easily caused by heavy and prolonged vaginal bleeding; (3) infertility, which can reach 22% to 66%, including 90% of those under 40 years of age.121 Physical examination is usually abnormal, but those with prolonged vaginal bleeding are anemic. The physical examination is often unremarkable. Endometrial atypical hyperplasia is a precancerous lesion. An accurate clinical diagnosis should be made and an individualized treatment plan should be developed, taking into account symptoms, signs and histological examination. Hysteroscopic endometrial multipoint biopsy and localized electrosurgery of the endometrium and superficial myometrium are important guides in the diagnosis of endometrial atypical hyperplasia, especially in young women with preserved fertility requirements. Pharmacological treatment is effective in most patients, but close follow-up is required. Hysteroscopic endometrial resection can be used as an intermediate transitional measure between pharmacological and hysterectomy treatment in selected patients with atypical endometrial hyperplasia who are eligible for close long-term follow-up.