Immature fish and young females were sex reversed using hormonal induction in two consecutive years. In the first year one permanent male was obtained. Collected sperm of both years ranges from 30 μl to 300 μl and cell concentration varies from 3 to 6.5 x 109 spermatozoa/ml. Atlantic dusky grouper can successfully be induced to functional males with 17α-methyltestosterone implants.