This study analyses six microsatellite markers on hybrid breeders aiming to produce monosex tilapia. Three hybridizations between species and strains are male O. niloticus Israel x female O. aureus Israel, male O. niloticus Taiwan x female O. aureus Israel, male O. niloticus Taiwan x female O. aureus Chinese that produced 72-100 percent, 74-100 percent, 43-100 percent male ratios respectively and 25 families in each hybridization. Parents produced higher and lower than 95 percent male in progeny were separated and analysed by six sex-linked microsatellites. As result, UNHI04, UNH995 and GM354 had specific alleles related to all-male ratios (p0.001). These alleles could be used to select broodstocks for hybridization producing all-male tilapia eventhough they need to be tested for consistent inheritance.