The present application relates to a method for cleaning, detoxifying and cells and tissues preservation of a fresh animal liver, comprising the following steps: taking out a whole fresh liver from an animal body quickly and removing the gallbladder, with blood vessels in first porta hepatis of the liver being retained; dissecting quickly and determining portal vein, biliary tract, hepatic artery and upper and lower ends of the inferior vena cava, and then inserting disinfected medical catheters into blood vessels of the portal vein, the biliary tract and blood vessels of the hepatic artery; perfusing a perfusate into the catheters, eliminating macrophages and other immune cells containing a large number of toxins, blood and harmful substances in the liver continuously and flushing bitter bile out from the biliary tract meantime; and completing processing of the liver when the fresh liver becomes white from blood red. It can be guaranteed that cells and tissues of the liver are not damaged as far as possible, and toxins, blood and harmful substances in the liver can be eliminated after the liver is treated by the method.