Abstract: Animal experiments were crried out on respiratory support with venovenous（vv） bypass and extracorporeal membrane oygention（ECMO）.The following results were obtained 1, Arterial blood gas was well maintained during 30 hours observation period in acute hypoxic and hyperca-pnic dogs.2,Prolonged ECMO has slight influence on hematological parameters.3,The postop-erative lung compiance was a little lower than the preoperative values, though it was stable du-ring bypass.4, Blood viscosity fell markedly at low shear rate.However,red blood cell deform-ability was found to be abnomal. 5,The heart,lung,kidney and adrenal of perfused animalsshowed no microscopic abnormalities.