Amenorrhea is one of the foremost concerns encountered by women. The most common cause of amenorrhea is hypothalamic, hyperprolactinemia, ovarian failure, and polycystic ovarian syndrome (PCOS). Primary amenorrhea is frequently the result of a genetic or anatomic abnormality. The evaluation of amenorrhea begins with a cautious history and physical examination. The majority of girls with Turner syndrome are < 135 cm in height. In India as seen in another place it can occur among sisters assuming a genetic backdrop as etiology. In Müllerian dysgenesis 46, XX karyotype is related with normal female serum testosterone concentrations. Serum prolactin and thyrotropin should be measured if FSH is low or normal, especially if galactorrhea is present. The reduction in AMH concentrations has newly been reported as a reliable marker for the evaluation of the ovarian impairment caused by chemo-or radiotherapy. Treatment of primary amenorrhea is directed at correcting the underlying pathology. Gonadal dysgenesis and treatment with growth hormone will help to attain a final height > 150 cm. This chapter also explained about secondary amenorrhea, hypothalamic amenorrhea, hyperprolactinemia, etc.