A total number of 32 NZW buck rabbits (5 months old and body weight of 2.5 + 0.02 kg) were used in this study. The experiment continued for 12 months and divided into two periods of cold (November to April) and hot (May to October) climatic conditions.Bucks were individually housed and fed ad libitum diet containing 16.5% crude protein, 13.1% crude fiber, 2.5% fat and 2600 K cal/kg digestible energy.Rectal temperature (RT) and respiration rate (RR) were recorded biweekly in bucks at random through cold (16 bucks) and hot (16 bucks) conditions. Corticosterone (Cor) hormone was determined. Ejaculate volume (ml), sperm concentration (x10⁶ ml), dead and abnormal spermatozoa (%), sperm motility (%) and hydrogen ion concentration (pH) were determined. Performance of bucks included fertility rate (%), number of services per conception, litter size and weight at birth was estimated. Rectal temperature (RT) of bucks under hot condition was significantly higher than that of bucks under cold condition. Respiration rate (RR) of bucks during hot conditions significantly increased by about 51% than that of bucks under cold conditions. Hot conditions associated with significantly increase (about 27%) in corticosterone concentration in plasma of bucks. Under hot climatic condition, it was observed that ejaculate volume, sperm concentration and sperm motility % were significantly decreased, however dead sperm% and hydrogen ion (pH) were significantly increased. Climatic condition had no significant effect on sperm abnormalities%, fertility%, number of services per conception, litter size and weight at birth.