Persistent hyperplastic primary vitreous (PHPV) is a rare ocular disorder caused by the incomplete regression of primary vitreous with the abnormal persistence of hyaloid vasculature. It is the second most common cause of leukocoria after retinoblastoma. Aim of this work is to report the case of unilateral PHPV in a 6 months old child. We will describe the main ocular, echographic and magnetic resonance findings, that are essential to conduct a right differential diagnosis.