Abstract: Objective To evaluate the application of continuous invasive intracranial pressure (ICP) monitoring in the treatment of posttraumatic acute diffuse brain swelling (PADBS). Methods A total of 113 PADBS patients underwent ICP monitoring and treated according to the monitoring results, and their prognosis was retrospectively analyzed. Results In the current study, 32 patients with normal or mildly elevated intracranial pressure (ICP 15—22 mmHg) underwent comprehensive treatment of neurological severity and all recovered well. Then, 31 patients with moderately increased intracranial pressure (ICP 23—40 mmHg) were given comprehensive treatment of neurological severity and their intracranial pressure was effectively controlled, including 17 cases with good recovery, 9 cases who were mildly disabled, and 5 cases who were severely disabled. There were 50 patients with severely increased intracranial pressure (ICP>40 mmHg) who underwent comprehensive treatment of neurological severity, where 24 patients underwent unilateral craniotomy and decompression surgery, with 15 good recovery cases, 5 severely disabled cases, 3 cases in the vegetative state and 1 case of death. The other 26 patients underwent bilateral craniotomy decompression, including 5 good recovery cases, 2 cases who were mildly disabled, 5 cases who were severely disabled, 8 cases in the vegetative state, and 6 cases of death. Conclusions The use of ICP monitoring in PADBS treatment can dynamically understand the changes in intracranial pressure, avoid unnecessary bilateral frontal-temporal cranial bone decompression, reduce its severe disability rate and mortality, and improve the cure rate.