Common dentex offers favourable prospects for farming in the Mediterranean area. The effect of the photoperiod on survival, growth and inflation of the swim bladder in dentex larvae has been studied in larval culture, from hatching to day 22, comparing 6 different light:dark regimes: 24:0, 18:6, 12:12, 6:18, 4:8 plus 4:8 and 0:24. Experiments were conducted in circular 1 m3 tanks in open circuit. Larvae cultured with photoperiods of 0:24, 6:18 and 4:8 plus 4:8 died before day 15. The best results in growth, survival and swim bladder inflation were found with the 18:6 photoperiod.