Objective To study the therapeutical effect of Peritoneal Lavage in Patients with Severe Acute Pancreatitis.Methods By retrospective fourty five SAP patients from May 2002 to January 2008 were enrolled,and 23 patients were chosen for peritoneal lavage by dual lumen catheter,22 patients received routine treatment only were taken as the control group.The therapeutical effect was compared in two groups.Results After peritoneal lavage,The time for abdominal pain relief and abdominal distention,average days of hospitalization was significantly shorter in the peritoneal lavage group than that in the control group( P < 0.01 ).The APACHE Ⅱ scores decrease,hyperamylasemia was shorter in the peritoneal lavage group than that in the control group(P <0.05 ).The total incidence of complications including acute renal failure,ARDS,SHOCK,infected,case fatality was lower in the peritoneal lavage group than that in the control group.Conclusion To raise the therapeutical effect,decrease the incidence of complications and mortality in patients with Severe Acute Pancreatitis,Peritoneal Lavage in time was a utility meas. Key words: Severe Acute Pancreatitis; Peritoneal Lavage