Objective: applying techniques of measuring trans-parenchymal intracranial pressure and estimating the role of measuring intracranial pressure in severe traumatic brain injury patients. Material and method: forward and crosssection describing research in 34 severe traumatic brain injury patients who were set up machine to measure trans-parenchymal intracranial pressure in neurosurgery and ICU department of Viet Duc Hospital from 01/2011 to 06/2011. Results: Intracranial pressure usually changes in the 3rd day. after accident: in the group of died patients, ICP varied between 19.4 and 32.2 mmHg. Group of good recovery patients has average ICP index decreases from 31 to 26.9 mmHg in the 3rd day after accident. There were many reducing ICP factors: ventilation helped ICP decreasing 26.5 percent, diuretic drugs diminished 35.3 percent of ICP, patient's position helped reducing 32.4 percent of ICP, operation reduced ICP in 100 percent of patients. Surgical indications: there were 20 of 34 patients indicated to operate and death proportion is 10 percent. Outcome: 17.6 percent of patients has ICP higher than 40 mmHg, death rate is 33.3 percent. 70.6 percent of patients has ICP varies between 20-39 mmHg, death rate is 15 percent. Conclusion: this method was safe and simple, there was no complication, include: hemorrhage, infection, so we could carry it out in patient's room.