Objective: Review epidemiological, clinical, para clinical factors affecting the outcome of traumatic brain injury (TBI) due to traffic accident. Materials and methods: Retrospective study of 318 TBI patients due to traffic accidents in Viet-Duc Hospital, evaluate the outcome of TBI with the Glasgow Outcome Scale after '6 months and compare the outcomes between relating groups. Results: The TBI generally affects men (83.6 percent), people in working age (83.7 percent). 44.5 percent of patients do not wear a helmet at the time of accident, specially all of the patients under 16 years old do not wear a helmet. According to the GCS, 45 percent of cases are mild TBIs, 35.5 percent are moderate TBIs and 19.5 percent are severe TBIs. The outcome is worse in patients who have the following characteristics: non helmet wearing (OR = 2.29, P = 0.018), GCS 3-8 (OR = 11.6
P 0.001), CT-scan image showing a diffuse lesion of grade III or IV (OR