Contents Female cats are known to be seasonal breeders and male cats annual breeders. Despite this, there are limited data on the influence of breeding season (BS) on hormone concentration and semen quality in the male cat. This study compared plasma concentrations of LH and testosterone ( T), and semen quality during the non-breeding season (NBS) and BS in five male cats subject to natural hours of daylight but a constant environmental temperature. Plasma LH and T concentrations were higher during the BS in 2/35 and 3/5 cats, respectively, although when comparing both hormones combined, values were higher during the BS than the NBS in all cats (p < 0.01). There were no significant differences in the percentage of abnormal sperm between the cats. Overall, semen quality was superior during the BS with larger semen volume in 2/5, sperm motility in 2/5 and sperm viability in 3/5 cats. Although there was a clear seasonal effect on hormone secretion and semen quality, during the NBS all cats were likely to have been fertile.