Reactive oxygen and nitrogen species (RONS) are necessary for the physiological function of sperm. Its concentration has to be kept on a level without the damage of cells. If this level is overdrawn sperm has pathological effect on many biological structures in the form of oxidative stress. Antioxidants have a key role for keeping of this balance. Oxidative stress is an important factor which causes problems with male fertility. The survey article is complexly concerned with the influence of RONS and antioxidants on male fertility. It outlines some possibilities of treatment and research on this actual issue of assisted reproduction.