PURPOSE: To report a case of retinoblastoma successfully treated by contact transscleral photocoagulation with a diode laser. METHODS: In an 18-month-old girl, a small (6.6 × 4.3 × 3.2-mm) discrete retinoblastoma anterior to the superotemporal arcade in the right eye was treated with transscleral photocoagulation using a diode laser (810 nm) and a fiberoptic probe. RESULTS: The tumor regressed after photocoagulation, leaving a pigmented chorioretinal scar. There was no regrowth of the tumor 12 months after photocoagulation. CONCLUSION: Contact transscleral photocoagulation with a diode laser may be a viable new treatment for small retinoblastoma.