Objective: To study and analyze the risk factors of brain hernia after severe craniocerebral injury and put forward early warning intervention suggestions. Methods: The clinical data of 120 patients with severe craniocerebral injury admitted in Suzhou Hospital of Anhui Medical University from June 2018 to June 2021 were analyzed retrospectively, and the incidence and mortality of brain herniation were counted, the risk factors of brain herniation were summarized, and the composition ratio of possible influencing factors between the concurrent group and the uncomplicated group was compared, and the logistic regression analysis was carried out. Results: There were 33 cases of brain herniation after operation, the total incidence of brain herniation was 27.50%, and the mortality rates of the complicated group and the non complicated group were 27.27% and 11.49%, respectively, there were statistical difference between the two groups (=4.470，P=0.035). The age > 60 years old, smoking history, preoperative GCS≤ 6 scores, atrial fibrillation, hyponatremia, preoperative pressure of basal cistern, postoperative mannitol half volume, lumbar puncture and postoperative intracranial hematoma in the complicated group were significantly higher than those in the uncomplicated group (P < 0.05). According to logistic regression analysis, age > 60 years old, smoking history, postoperative mannitol half amount, combined with atrial fibrillation, lumbar puncture, preoperative pressure of basal cistern, combined with hyponatremia, preoperative GCS≤ 6 scores and postoperative intracranial hematoma were all independent risk factors of cerebral hernia, respectively (OR=2.989, 3.058, 3.284, 3.414, 3.476, 3.504, 4.450, 5.217, 5.441, P＜0.05). Conclusion: The patients with severe craniocerebral injury have higher risk of brain herniation and more risk factors. It is necessary to strengthen early warning and timely intervention to avoid the occurrence of brain herniation.