One of the most important efficiency is fertility in animals. Especially DNA damage is important factor in fertility. However sperm DNA damage has been shown in many species. Decreasing in spermatozoa quality and also death embryo prior to implantation time and abnormal embryonic development can be caused by sperm DNA damage. Sperm DNA damages have occured in the sperm DNA at different levels due to various endogen and exogen reasons. Evaluation of spermatozoon DNA damage leads to improve many techniques among the biotechnological innovations may either solve some problems of fertility, especially in embryo transfer and in vitro fertilization or plays an important role on the desired breeding and artificial insemination programs. In this article, the effects of some factors on spermatozoon DNA damage and the use of the single cell gel electrophoresis technique in the damage determination are presented in the lighting of the related recent researches.