Abstract： Objective To investigate the timing of surgical operation and prognosis of patients with severe biliary pancreatitis (SBP).Methods The patients were classified into three groups according to the interval between disease onset and operation time ( ＜7 d, 7 ～ 14 d, ＞ 14 d).The incidence of complications and mortality were compared among the 3 groups.Results A total of 32 patients of acute pancreatitis due to biliary tract diseases between 2006 and 2009 were included, and there were 15 males and 17 females with a median age of 51 years old.9 patients received operation within 7 days of disease onset and all of these patients were complicated with biliary obstruction;12 patients received operation between 7 ～ 14 days of disease onset and all of these patients were non-respondent to early non-operative management.11 patients received operation after 14 days.The complication rates in the three groups were 44.4% , 50.0% and 45.5%, respectively, the difference was not statistically significant ( P ＞ 0.05 ).The mortality rates in the three groups were 11.1%,16.7% and 18.2%, respectively, and the difference was not statistically significant ( P ＞ 0.05 ).Conclusions The management of SBP should be individualized.Patients with biliary obstruction, suppurative cholangitis or non-respondent to early non-operative management shall be managed surgically, and this is critical to decrease the mortality rates and improve prognosis.