Puberty is an essential physiologic process that is characterized by the appearance of secondary sexual features. Secular changes in puberty occur from one generation to another and need to be documented. The assessment of pubertal stages in a child is only useful if recent and reliable reference data from the same population is available for comparison. The study aimed to profile clinical normative sexual maturity characteristics for children in Calabar, South-South Nigeria.A cross-section of primary and secondary school pupils aged 6-18 years in the city of Calabar, Nigeria were randomly selected for the study. Sexual maturating rating was assessed using the pubertal staging for breast development and pubic hair as described by Marshall and Tanner (Tanner staging). Testicular volume in boys was measured using the Prader orchidometer. Menarche and "voice break" were established by recall of the event by the girls and boys respectively.A total of 2,830 children were seen, 1542 (54.5%) boys and 1288 (45.5%) girls. The mean age of onset of pubic hair was 11 years in both boys and girls. Pubertal testicular volume of 4 mls was seen in boys at a mean age of 11 years. Breast development in girls occurred at mean age of 11 years and menarche at 13 years.in this study, the onset of puberty is occurring at an earlier age than previously reported in Nigeria with a secular trend of a decreasing age at onset of puberty. These sexual characteristics are rather occurring at similar ages reported from western countries.