Abstract: Hyperbaric oxygenation could inhabit the growth and progression of malignant tumor. It could increase the oxygen delivery to tumors and induce cell cycle synchronization of tumor cells. As a safety and effective radiosensitive protocol, it can be used with radiation therapy to enhance the efficacy of clinical treatments. At the same time, hyperbaric oxygenation was also a main treatment of late radiation injuries. But its prophylactic effect on radiation complications requires further studies.