Rooster semen cryopreservation is a useful method to utilize semen samples for artificial insemination in commercial flocks, but with use of the freezing-thawing process there is a reduction in the quality and fertilization capacity of rooster spermatozoa post-thawing. The aim of the current study was to investigate the efficacy of the mitochondria-targeted antioxidant Mito-TEMPO on rooster sperm quality and fertilization capacity after conducting the freezing-thawing processes. Semen samples were diluted and there were five equal aliquots supplemented with 0, 0.5, 5, 50 and 500 μM Mito-TEMPO. Semen samples were subsequently cryopreserved in liquid nitrogen. After thawing, sperm motility, lipid peroxidation, membrane functionality, normal morphology, mitochondria active potential, acrosome integrity, viability, apoptotic-like changes, DNA fragmentation, hydrogen peroxide concentration and fertilizing capacity were evaluated. Supplementation of Lake medium with 5 and 50 μM Mito-TEMPO resulted in greater (P ≤ 0.05) total sperm motility, progressive motility, average path velocity, membrane functionality, mitochondria active potential, acrosome integrity and viability compared with semen of the other groups. Lipid peroxidation, late apoptotic-like changes, DNA fragmentation and hydrogen peroxide content, however, were less (P ≤0.05) in semen samples supplemented with 5 and 50 μM Mito-TEMPO compared to other groups. Furthermore, fertility percentages were greater when there was supplementation with 5 and 50 μM Mito-TEMPO compared to the control group. Mitochondria-targeted antioxidant Mito-TEMPO could be included in semen extender before cryopreservation to improve quality and fertilization capacity of rooster semen after thawing of cryopreserved samples.