A 59-year-old woman underwent enucleation for choroidal melanoma. She had a late recurrence of the melanoma, which was treated with surgery and radiotherapy. Nine years after radiation treatment, she presented with pain and an orbital mass. Biopsy of the mass revealed an osteoblastic osteosarcoma. This report describes the late recurrence of choroidal melanoma and subsequent radiation-induced osteosarcoma. The risk of radiation-induced malignancy should be considered in all patients receiving radiotherapy. Despite yearly review, osteosarcoma was diagnosed only when the patient had symptoms, thus raising questions about the merits of long-term follow-up in detecting recurrence or emergence of secondary tumors.