Objective In addition to a fundamental role in very diverse processes such as vision and growth and differentiation of numerous types of cells,vitamin A(retinol) is involved in the regulation of testicular functions in rats and mice.An excess of vitamin A leads to spermatogenetic disorders,and its deficiency induces early cessation of spermatogenesis.Furthermore,mouse mutant are steriles.In this review,the location of retinoic acid receptors,the metabolisms of action in the testis and its effects on fetal and adult testis are summarized.