Acute hemorrhagic and necrotizing pancreatitis (AHNP) was induced by injection of sodium taurocholate into pancreatic and biliary duct of rats. TNFα MCAb was infused intravenously 15 minutes before pancreatitis was induced, and plasm TNFα level, serum lipase level and pancratic pathologic changes were tested.Results: the amount of ascites, serum lipase level and palsm TNFα level were significantly incresed and severe pancreatic pathologic changes was induced after AHNP, as compared with those in the control group .However, plasm TNFα level was not elevated after administration of TNFα MCAb, and the amount of ascites and pathologic damage to the pancreas were markely reduced. The animal fatality was reduced too. Conclusions: these suggest that TNFα play an important role in the pathogenesis of AHNP, and TNFα MCAb have a certain therapeutic effect on AHNP in rats.