Summary: The relation between the height of adolescent haemophiliacs and their bleeding frequency has been studied. 45 haemophiliacs aged 10-19 years were divided into 3 groups: small, medium and tall, using a Height Standard Deviation Score. The average bleeding frequency per 100 days in the group of small haemophiliacs was 8.71 ± SD 4.47, in the medium height group 10.18 ± SD 6.71, while the tall individuals bled in average 15.97 ± SD 3.15 every 100 days. There was no relationship between age and bleeding frequency.