An unusual case of a presacral ectopic choroid plexus cyst in a neonate is described. After birth, a soft lump was noticed at the left buttock. Imaging studies including sonography and magnetic resonance imaging demonstrated a presacral cystic lesion extending to the buttocks, composed of several septated cystic masses with no connection to the spinal canal or rectum. After total resection, the tumor was diagnosed as an ectopic choroid plexus cyst. To our knowledge, this is the first case report in the English literature of a presacral ectopic choroid plexus cyst.