Analysis of patients with chronic pancreatitis (CP group) and biliary disease (BD group) in Changhai Hospital from January 2011 to May 2015 were conducted. Difference of PEP incidences between BD group and CP group, as well as between M-ANNHEIM subcategories were calculated by chi-square test or Fisher's exact test. The predictive and protective factors for PEP were investigated by univariate and multivariate analysis.