Background: Pubertal growth data in Thai children has been reported as cross-sectional studies. There is no longitudinal study in Thai children. Objective: Investigate the longitudinal growth data in normal Thai children including the relationship between age at pubertal onset and other growth parameters. Material and method: Eighty-eight normal children (44 boys, 44 girls) were longitudinally assessed for the growth and puberty until they reached their final adult height. Pubertal staging was assessed by the Tanner method. Results: Mean age of pubertal onset was 10.2 ± 1.2 years for girls and 12.2 ± 1.0 years for boys. Total pubertal height gain was 18.3 ± 4.0 cm for girls and 22.3 ± 4.4 cm for boys. Total pubertal height gain had a negative correlation with age at pubertal onset for girls, but not for boys. Conclusion: The onset of puberty was not much changed from previous studies. Girls with early puberty had a higher pubertal height gain. This might be due to a compensatory mechanism. These longitudinal growth data can be used as a reference in clinical practices for Thai children.