A 50-year-old man presented with a reddish, well-vascularized mass in the region of a nasal iridodialysis of his left eye, pushing the whole iris in this sector forwards; the mass had a pinkish, partly cystic appearance in the pupil. The tumour was transparent on diaphanoscopy. A-scan sonography revealed a solid tumour of the ciliary body with partial retinal detachment suggesting a malignant melanoma. Fluorescein biomicroscopy did not confirm this suspicion. The enucleated eye demonstrated a malignant teratoid medulloepithelioma of the whole nasal and lower ciliary body, infiltrating the deep iris stroma, the anterior choroid, the neighbouring vitreous body and spreading along the inner retinal surface back to the equator of the eye. The occurrence of medulloepithelioma in adult and senior persons is rather exceptional and this is the reason for this publication.