Abstract: Soft tissue sarcomas (STS) consist of a heterogeneous group of rare malignancies with mesenchymal origin. Surgical resec-tion is the primary treatment for STS, but radiation therapy (RT) also plays an important role in the treatment. Radiotherapy for STS has advanced significantly over the past 50 years. Both preoperative and postoperative radiotherapies are equivalent in local control but are associated with different toxicity profiles. Boost techniques for STS include brachytherapy, intraoperative radiation therapy (IORT), and external beam. Long-term toxicities of RT to normal tissues have been reduced because of improvements in image guid-ance and intensity-modulated radiotherapy, which significantly increase the precision and delivery of RT. This review discusses RT tech-nologies and their acceptable treatment principles.