The Anti-Mullerian hormone /AMH/ is a glycoprotein of the transforming growth factor-beta superfamily. It induces regression of the Mullerian ducts during the male sex differentiation. The hormone actions occur through serin/threonin kinase receptors-AMHRI and AMHRII. The AMH and AMHRII gene defects in men cause the syndrome of oviductus persistens. Recent findings accent not only on the hormone fetal role, but also on the postnatal AMH secretion, especially in women. The hormone is produced mostly by granulosa cells of the preantral and small antral follicles. Therefore, its levels in women after puberty are similar to those in males and it could be used as a marker for the ovarian reserve and preantral and small antral follicle count. In this review, we discuss the role of AMH in the follicular development, the polycystic ovary syndrome and the ovarian ageing. After gathering all data, it could be assumed that in the future AMH will be widely used in the clinical practice as a marker of the ovarian function.