Intracavernous elastic fibres may play a role in human erectile tissue compliance and elasticity. Using computerized image analysis we have measured objectively the percentage of elastic fibres in corpus cavernosum tissues in both potent and impotent men. Twenty-two penile biopsies were performed in 5 potent and 17 impotent patients due to vascular disease. The mean percentage of elastic fibres was 9% in normal patients. In 12 patients with venous leakage a significant decrease in the amount of elastic fibres of 5.1% was observed and in 5 patients with arterial disease it was 4.3%. No correlation between the reduction of the elastic fibre quantification and age was observed. Change in elastic fibre content may alter the relaxation properties of cavernosal tissue and play a role in the development of erectile dysfunction.