A craniopharyngioma detected in utero using ultrasound is reported from the Depts of Neurosurgery, Neonatology, Pathology, and Obstetrics and Gynecology, New York University Medical Center, New York, NY. The obstetric ultrasound study performed because of premature labor at 35 weeks showed polyhydramnios and macrocephaly secondary to an intracranial, calcified lobulated mass. A CT scan performed at 2 hrs. of life demonstrated a calcified intracranial mass extending to the base of the skull. The infant suffered cardiorespiratory arrest and died at the second day of life. At postmortem examination, the suprasellar mass was a granular tumor with multiple cysts filled with green mucoid material. Microscopically, the tumor showed branching cords and pallisading of epithelial cells, focal calcifications, and an inner zone of stellate cells, an appearance diagnostic of craniopharyngioma. The authors uncovered only four other reports of congenital intracranial neoplasms diagnosed prenatally using ultrasound. Three were teratomas and one a dysplastic mass. Calcifications have been observed in teratomas and meningiomas in utero and are not pathognomonic of craniopharyngioma. Low set ears and Polydactyly are reported as associated congenital anomalies. Polyhydramnios occurred in all five cases of neonatal brain tumors diagnosed antenatally by ultrasound. Radical excision of the tumor in the neonatal period was not advised. [1]