A whitish pupillary reflex (leukocoria) indicates abnormal reflection from intraocular pathology. In a child, leukocoria may be a sign of serious and even life-threatening eye disease (retinoblastoma), but the most common cause is congenital cataract. Both diagnoses require immediate referral to an ophthalmologist. Leukocoria is best detected by evaluating the reflex from the pupil with a handheld ophthalmoscope. We here present a case story of an infant with leukocoria that proved to be caused by unilateral congenital cataract.