Objective: To explore the clinical value of bilateral balanced frontotemporoparietal decompressive craniectomy (bbDC) in severe diffuse traumatic brain injury by comparison to the unilateral frontotemporoparietal decompressive craniectomy (uDC). Materials and Methods: Twenty three patients with severe diffuse traumatic brain injury from April 2015 to December 2019 were selected, including 10 cases underwent bbDC (bilateral group) and 13 cases underwent uDC (unilateral group). Compared with the postsurgical intracranial pressure (ICP), cerebral perfusion pressure, cerebral blood flow volume, postsurgical imaging score, the occurrence of complications as well as the 6 month outcome (Glasgow Outcome Scale, GOS) of two groups. Results: 1. The postsurgical ICP was lower in the bbDC group than in the uDC group, while the postsurgical CCP and cerebral blood flow volume were higher in the bbDC group than in the uDC group. 2. Postsurgical imaging scores of the bbDC group were lower, indicating that the decompression effect of bbDC was more exhaustive than that of the uDC group. 3. The incidence of intraoperative acute cerebral bulging was lower in bbDC group than in uDC group. 4. The bbDC could effectively reduce the proportion of patients with the worst prognosis (deadþvegetative state). Conclusion: For patients with severe, diffuse traumatic brain injury combined with bilateral or unilateral pupil dilation, bilateral balanced decompression craniotomy is an effective method, which should be performed as soon as possible. As compared to unilateral decompression, the decompression effect on the brainstem is more thorough; the incidence of acute cerebral bulging, postoperative incisional hernia, and postoperative cerebral infarction involving a large area are reduced. ICP can be better controlled, cerebral perfusion pressure and cerebral blood flow increases, improving the patient's survival rate, quality of life, and prognosis.