The mean age at natural menopause and its determinants among Shirazi women (southern Iran) was calculated. The data were obtained from a population- based cross-sectional study carried out in the year 2000. Interviews were carried out and observations made on 948 women who had incurred natural menopause. They were randomly chosen using postal zones housing sample framework of Shiraz. Mean±SD age at menopause in the studied group was 48.3±5.3 (95% CI: 48.0-48.6) years with a median of 49.0 years. Arm circumference, height, weight, BMI, place of birth, handedness, ancestry, family background, level of education, level of daily physical activities, smoking habit, history of abortion, age at first marriage, age at first full-term pregnancy, menstrual cycle interval/duration, age at menarche, dysmenorrhea, mid-cycle spotting, were rewrded. It was found that the number of pregnancies were not significantly related to age at menopause. Age at natural menopause significantly correlated with menstrual cessation pattern, age at last full-term pregnancy, consanguinity of marriage, place of birth, and use of hormones before menopause.