Objective To study the influence of different starting time of hyperbaric oxygen(HBO) therapy on severe brain injury patients.Methods 60 cases of acute cerebral infarction patients were divided into 2 groups,namel 48 hours to 7 days group(group A) and 8 days to 15 days group(group B) after injury.Fugl-Meyer assemment and modified Barthel index were employed to assess the patients before and after HBO for 30 days in the 2 groups.Results After 30 days of HBO therapy the Fug-Meyer assemment and modified Barthel index in the A group were better than those of B group,there were significant differences between the 2 groups(P