OBJECTIVE To determine the incidence of endometrial hyperplasia and to analyse the management of patients with this disorder. METHOD Retrospective descriptive study at the Department of Obstetrics and Gynecology, Ramathibodi Hospital. The medical records of patients with endometrial hyperplasia from 1990 to 1995 were analysed. Descriptive statistic was used. RESULT Medical records could be obtained in 87 per cent of cases. Incidence of endometrial hyperplasia was 1 per cent of gynecological out-patients and 11 per cent of uterine curettage. Half of the patients had cystic hyperplasia. Main treatment options of patients with cystic hyperplasia were expectant and progestogen therapy. The major treatments of adenomatous hyperplasia were progestogen and hysterectomy. Most patients with atypical hyperplasia underwent hysterectomy. Most of the patients with expectant or hormonal therapy have recurrence of abnormal uterine bleeding. CONCLUSION Endometrial hyperplasia is not uncommon in gynecological practice. All gynecologists should be familiar with the pathophysiology and the natural history of this disorder. The unopposed estrogen stimulation should be investigated and corrected. Treatment options should be tailored to individuals according to disease grading, age of the patient and desire of pregnancy. Long-term follow-up until menopause is mandatory to prevent the excessive uterine blood loss and the progression to carcinoma.