To estimate the distribution of age at menarche and investigate menstrual patterns and symptoms among adolescent Jordanian girls.Menstrual status data were collected from 596 secondary-school students from the Amman area via a self-administered questionnaire. Descriptive statistics, cross-tabulation, and correlation coefficient calculations were used where appropriate, and probit analysis was applied to estimate mean±SD age at menarche.The students' mean age was 15.7±1.5years. Mean age at menarche was 13.1±1.1years for those who recalled it and 12.8±1.4years per the probit analysis. Menstruation duration was 4 to 7days for 73.6% of the students, and it was more than 7days for 2.2%. Mid-cycle pain was reported by 30.9% and dysmenorrhea by 37.6% of the students, 8% of whom needed to miss school 1day per cycle. Body mass index was correlated with age at menarche (P=0.002).The mean age at menarche was close to that reported in studies from Europe and the USA, but it was younger than the age reported in studies from Africa.