Fayoumi birds were supplemented with 0 (control), 1, 2, 3 and 4 per cent elementary sulphur in feed from 56 days to 140 days of age. Clinically, faeces in birds fed by 2, 3 and 4 per cent sulphur were not well formed. Mortality did not differ significantly between treatments. Sulphur treatment induced a significant decrease in live body weight which was dose-related. Liver and kidneys were affected markedly. Heart and spleen were not affected. Testes weight was relatively lesser in male sulphur treated birds than the control males. The number of ovarian follicles was lesser in female sulphur-treated birds than the control females. The study suggests that prolonged use of sulphur may influence live body weight, some visceral organs and gonads in birds.