Severe corneal ulceration related to self-inflicted injury in the presence of congenital corneal anaesthesia is described in four boys under 2 1/2 years of age. The ulcers had failed to heal until it was recognised that the children were scratching their own eyes. The application of arm splints allowed rapid healing. Although corneal ulceration is a recognised complication of congenital corneal anaesthesia, this preventable cause of the ulceration has not previously been recognised. In two cases there were isolated recurrences which healed quickly with the reapplication of splints. All four children had good vision initially, and, although there were no overt gross development abnormalities, two had neurological signs on detailed investigation suggesting cerebellar or brain stem malformation and one had unilateral anophthalmos, talipes equinovarus, and patent ductus arteriosus. All the children showed normal intellectual development. Whether the eye scratching behaviour was the primary cause of the ulceration or merely an aggravating factor, the identification of this abnormal behaviour is important in any child with idiopathic corneal ulceration, as even in the presence of congenital corneal anaesthesia the eyes heal quickly with effective splinting of the elbows. It is therefore important to test sensation of the cornea and face and to consider the possibility of self-inflicted injury in children with refractory corneal ulceration, as in our cases there were no other consistent diagnostic features.