- Oxidative stress is induced by reactive oxygen substances (ROS) that are known to affect male fertility. The aims of this study were to prospectively investigate and characterize total antioxidant and specifically polyphenols concentrations and their relations to sperm quality and fertility treatment success. During their infertility treatment, sixty-seven males were prospectively recruited to this study. After separation of the sperm from the semen sample, the semen fluid samples antioxidants and polyphenols concentrations were determined. Antioxidant concentration was significantly associated with sperm concentration and total motile count. Antioxidants concentration in the group of male with sperm concentration ≥ 15 × 10 6 was significantly higher than in the group of male with antioxidants concentration < 15 × 10 6 (830.3 ± 350 μ M and 268.3 ± 220 μ M, resp., p < 0.001 ). Polyphenols concentration did not differ between the groups of sperm concentration above and below 15 × 10 6 (178.7 ± 121 μ M and 161.7 ± 61 μ M, resp., p -NS). No difference was found between fertilization rates and antioxidants or polyphenols concentrations. This is the first study that reports on polyphenols concentration within semen fluid. More studies are needed in order to investigate polyphenols role in male fertility.