Uveoretinitis was observed in a 9-year-old girl 6 months prior to the clinical appearance of a pineal tumour. Surgical removal was not successful but biopsy revealed a parenchymal neoplasm with differentiated pinealocytes and absent mitotic activity. Some of the tumour cells contained S-antigen, rhodopsin, and serotonin. Systemic glucocorticoid therapy followed by radiation therapy caused considerable reduction in size of the tumour and a complete normalisation of all eye symptoms. This report demonstrates for the first time that a pineocytoma can occur together with uveoretinitis in humans. The latter resembles the experimentally induced autoimmune uveoretinitis described in animals. It is speculated that the retinitis might reflect an autoimmune response to S-antigen present in some tumour cells of the pineocytoma.