【Objective】To analyse period and effect of brain infarcted patients treated with hyperbaric oxygen.【Methods】The patients with moderate and severe brain infarction treated with hyperbaric oxygen were retrospectively studied.They were grouped by occasion of hyperbaric oxygen therapy,then the treated effects were compared.【Results】The rates of cure and inefficacy to the group of 24h,2~5d,6~9d,10d were 47.82%,9.52%,5%,0%;43.47%,61.90%,25%,15%;8.6%,28.57%,65%,75%;0%,0%,5%,10% respectively.【Conclusion】Brain infarcted patients treated in time with hyperbaric oxygen can get very good efficacy,if not in time the curative effect is not aparent,only some clinic improvement can be seen.