This study aimed to evaluate the effect of Spirulina platensis on sexual desire, semen quality, and biochemical and antioxidant parameters in blood and seminal plasma of APRI rabbit bucks. Thirty bucks were divided into three groups (10 in each). Bucks in the 1st, 2nd and 3rd groups daily received drinking water supplemented with 0, 150, 300 mg spirulina/l for one month (treatment period), respectively. About one month of treatment, semen was collected and evaluated twice/week for ten weeks (200 ejaculates/group). At the end of the experiment, biochemical constituents, enzymatic activity and antioxidants status in blood and seminal plasma, as well as blood plasma testosterone were analyzed. Also, does (n=20/group) were naturally mated with five bucks from each group. Net semen volume, pH value, individual motility, livability, membrane integrity and concentration of spermatozoa, total sperm output per ejaculate and semen initial fructose increased (P<0.05), while reaction time, abnormality and acrosomal damage decreased (P<0.05) by both spirulina levels compared with control group. In blood and seminal plasma, total proteins, globulin, glutathione, glutathione peroxidase, glutathione S-transferase and superoxide dismutase increased (P<0.05), while aspartate aminotransferase and thiobarbituric acid-reactive substances (P<0.05) decreased by both spirulina levels. Testosterone and albumin in blood plasma increased (P<0.05) by both spirulina levels. Pregnancy rate and litter size improved (P<0.05) in does mated by bucks treated with both spirulina levels. Spirulina platensis administration at a level of 150 mg/l in drinking water for one month, could be effectively used for improving semen quality, oxidative status and the fertility of rabbit bucks.