Abstract: 【ABSTRACT】Objective: To investigate the clinical effect of hyperbaric oxygen in the treatment of severe brain injury. Methods:100 cases of severe traumatic brain injury were randomly divided into control group and HBOT group, each of 50 cases. The control group was treated with operation and non operation treatment according to the condition, the HBOT group was treated with hyperbaric oxygen on the basis of the control group, and the indexes of the two groups after treatment were compared. Results: After hyperbaric oxygen therapy HBOT group patients with intracranial pressure was significantly lower than that of the control group (P＜0.05); hyperbaric oxygen treatment for 7 days, HBOT group cerebral blood flow were better than those of the control group (P＜0.05), HBOT group cerebral oxygen uptake rate were higher than those of the control group (P＜0.05). From the total efficiency, the HBOT group in June after the treatment was significantly higher than that of the control group (P＜0.05). Conclusions: The treatment of hyperbaric oxygen in patients with severe traumatic brain injury can significantly reduce intracranial pressure, improve cerebral blood flow, promote the rate of cerebral oxygen uptake, and improve the prognosis of patients with severe brain injury.