Juvenile xanthogranuloma (JXG) is a rare and usually benign disease occurring in early childhood. It causes skin and deep seated lesions, notably in the eye. We report a case of JXG in the iris of a 9-month-old infant. Examination under general anesthesia revealed megalocornea, iris xanthogranuloma occupying the entire anterior chamber and high intraocular pressure. Skin lesions on the left lid and on the back were also found. Ocular hypertension resisted medical and surgical treatment. Cyclodestruction was necessary. The incidence of JXG is low (0.4%). The iris is the most frequently affected ocular tissue. Early diagnosis is necessary to avoid complications. Moreover, JXG can be associated in rare cases with neurofibromatosis or leukemia which must be systematically searched for.