Abstract: Objective: To investigate the role of hyperbaric oxygen therapy on the hepatic artery ligated rat.Methods: Total 96 male Sprague-Dawley rats were randomly divided into three groups: contol group,the liver was freed from its ligaments and was reperfused.HAL group,the liver was freed from its ligaments and was reperfused,the hepatic artery was doubly ligated and cut.HAL+HBO,2h after HAL,Hyperbaric oxygen（HBO） treatment under 0.25MPa for 60 min twice daily was performed.Each group including 1 d,3 d,7 d,14 d subgroups.Liver perfusion was measured by laser Doppler flux.The biopsy were carried out for the histological examination.Results: Liver tissue blood flow decreased significantly from 4.58±0.42V to 3.32±（0.29）V after hepatic artery ligation（HAL） at 1day.There were significant differences among groups at postoperative day 14（（4.22±0.31））V vs（3.62±0.49）V,P＜0.01.microscopic studies showed significant hepatic cell hydropic degeneration and focal necrosis in HAL group.There were new blood vessels and no hepatic cell necrosis in HBO group.Conclusion: The application of HBO against hepatic artery ligation ameliorate liver perfusion and serum ALT.H-E staining showed liver injury was reduced by HBO.HBO may have some benefit effect on allograft post liver transplantation hepatic artery thrombosis.