Abstract: Background and Objective: Currently, there is paucity of information in tropical and sub-tropical conditions on the interaction effects of genotype, sex and stocking density on optimum broiler performance and carcass characteristics, since the recommended densities are based on researches in temperate environments. Therefore, the interaction effects of genotype, sex and stocking density on growth performance and carcass characteristics were investigated. Materials and Methods: Male and female Ross 308 and Cobb Avian 48 broilers were reared at stocking densities of 30, 35 and 40 kg BW m–2 over 42 days. Data were analyzed by a three-way ANOVA for a 3×2×2 factorial using the GLM procedure of Minitab 17. Results: During the entire period, genotype had no effect (p>0.05) on any growth performance traits. While, males consumed 8.5% more (p<0.01) feed, gained 11.5% more (p<0.01) body weight and were 10.9% heavier (p<0.01) at slaughter (day 42) than females. For stocking density, broilers reared at 30 kg BW m–2 consumed 9.0 and 12.8% more (p<0.01) feed, gained 7.4 and 9.4% more (p<0.01) body weight and were 6.8 and 8.7% heavier (p<0.01) at slaughter than those raised at 35 and 40 kg BW m–2, respectively. Except the reduction (p<0.05) in breast percentage weights with increasing stocking density, neither genotype, sex nor stocking density influenced (p>0.05) percentage weights of carcass parts. There were also stocking density×sex interaction effects (p<0.05) on feed consumption, genotype×stocking density interaction effects (p<0.05) on the relative weights of the wing and abdominal fat and genotype×sex interaction effects on 42 days body weight (p<0.01) and relative weight of the wing (p<0.05). Conclusion: The results showed that male Cobb Avian 48 raise at stocking density of 30 kg BW m–2 performed better in the sub-tropics specifically in winter.