PURPOSE: To review the current literature on the safety and efficacy of orbital radiation for the management of thyroid eye disease (TED). METHODS: A literature search was conducted last in February 2021 of the PubMed database to identify all articles published in the English language on original research that assessed the effect of orbital radiation on TED. The search identified 55 articles, and 18 met the inclusion criteria for this assessment. A panel methodologist then assigned a level of evidence rating for each study, and all of them were rated level III. RESULTS: Two large retrospective studies demonstrated the efficacy of radiation treatment, with or without corticosteroid use, in preventing or treating compressive optic neuropathy (CON). Three studies highlighted the role of orbital radiation therapy (RT) to facilitate the tapering of corticosteroids. Several other studies showed a possible role for RT to improve diplopia and soft tissue signs. CONCLUSIONS: Although no level I or level II evidence exists, the best available evidence suggests that orbital radiation, used with or without corticosteroids, is efficacious in preventing CON, improving motility restriction, and decreasing clinical activity in TED. Orbital radiation also may facilitate a corticosteroid taper. Together, these studies show that RT seems to modify the active phase of TED. Short-term risks of orbital radiation are minor, but long-term outcome data are lacking.