Abstract: Electromagnetic radiation exists generally in our living and working environment. Male reproductive system is highly sensitive to electromagnetic radiation， which may cause structural and functional injury of testis as well as sperm lesion in epididymis such as the reduction of sperm density and motility， increase of abnormality rate and ultrastructual alteration. Oxidative stress， abnormal energy metabolism and the changes of apoptosis-related protein expressions may be responsible for injuries of testis and epididymal sperms. Epidemiological investigations have demonstrated that electromagnetic radiation can cause the alteration of semen parameters and then result in the decline of sexual function and fertility.

Key words: Electromagnetic radiation, Testis, Epididymal sperm, Mechanism