Objective To explore the diagnosis and treatment of acute biliary pancreatitis (ABP) and when to operate. Methods 126 cases of ABP from Jan. 2005 to Dec. 2009 in our hospital were analyzed retrospectively. Results The cases number of the mild non-obstructive type, mild obstructive type, severe non-obstructive type, and severe obstructive type was 54, 33, 15, 24 respectively. 43 patients underwent early operation, 80 patients underwent postponed operation and three patients died preoperatively as a consequence of fulminat severe pancreatitis. 117 cases ( 92.86% ) were cured and 9 cases ( 7. 14% ) with severe acute pancreatitis died. Conclusion ABP should be treated according to its type. The key to reduce the complications and increase the cure rate is to determine the proper operation time according to the condition of individual patient.