Varicocele is the most common cause of infertility in men. The mechanism by which varicocele cause the variable effect on male infertility and is still unknown. Varicocele is found in 35 to 81 % of infertile men, and is one treatable form of male infertility. Although many advances have occurred in the treatment of varicocele, it still represents an important and challenging aspect of basic research (male reproductive physiology and endocrinology, pathophysiology, and pharmacology of reproduction and fertility) and medical practice for urologists, pediatric surgeons, and general physicians, to date. This review provides an overview of the epidemiology, Clinical classification and Immunological aspects of varicocele and discusses the indications for, and interpretation of Immunological aspects of varicocele.