In this review, we aim to examine the effect of extrinsic and intrinsic factors on spermatogenesis process taking into account a complex signaling pathway. Primarily, it is suggested that retinoic acid (RA) has a vital function in spermatogenesis process and it is considered to be essential for completion of spermatogonia into mature spermatozoa. In the present review, the key effects of retinoic acid (RA) on spermatogenesis process were evaluated in the perspective of studies done, particularly at molecular level. Thus, this review will provide re look the spermatogenesis process in an outlook of new studies. پرونده مقاله