The level of the products of lipid peroxidation measured as the thiobarbituric acid reactive substances (TBARS) and activity of enzymes of glutathione antioxidant protection system in spermatozoa were studied. It was shown that mean levels of TBARS in sperm cells of infertile men with oligozoo-, astenozoo-, oligoastenozoo-and leucocytospermia were 1.6-, 2.0-, 2.0-and 2.7-fold higher, respectively, compared with such levels in the fertile men. The glutathione peroxidase activity was decreased 2.2-fold in patients with oligozoospermia, 2.8-fold in patients with astenozoo-and oligoastenozoospermia and 3.8-fold in patients with leucocytospermia. It was found that glutathione reductase activity in patients with oligozoo-, astenozoo-, oligoastenozoo-and leucocytospermia were 2.3-, 1.6-, 1.7-and 3.3-fold lower than that in normozoospermic men, respectively. In addition, the glutathione transferase activity was decreased 1.8-2.1-fold in patients with oligozoo-, astenozoo-and oligoastenozoospermia and 5.0-fold in patients with leuco cytospermia in comparison with healthy donors. The most significant changes were observed in the infertile men with leucocytospermia. This manifestation could be explained by the fact that white blood cells stimulate the formation of reactive oxygen species, induction and development of oxidative stress in sperm cells.