Abstract: Oxidative stress can induce much more reactive oxygen species (ROS), which upset the balance between oxidation and antioxidant. The low level of ROS plays a role in regulating the physiological function of cells, whereas the abnormally high level of ROS can cause the damage of tissues and cells, such as abnormal signal pathways, energy production disorders, gene mutations and protein structure changes, and further affect the functions of cells, tissues, organs and even system. In male reproductive system, the high level of ROS causes serious damage in the reproductive organs and the germ cells as well. For instance, the high level of ROS induced the testicular damage in morphological structure and steroid syntheses. Oxidative stress may directly damage the structures of DNA, membrane lipids and proteins in germ cells, which greatly increases the deformity rate of sperm and eventually leads to male infertility. It is important to understand the ROS production in male reproductive system and its effects on male fertility, so as to discuss further  the pathogenesis of male infertility and the related antioxidant treatment.

Key words: Oxidative stress, Reactive oxygen species, Male, Genitalia, Spermatozoa