Endoscopic retrograde cholangiopancreatography (ERCP) is frequently used for diagnosis and therapeutic interventions in recipients of liver transplantation (LT) who develop biliary complications. Post–endoscopic retrograde cholangiopancreatography acute pancreatitis (PEP) is the most common major adverse event after ERCP; however, the frequency of PEP in LT recipients is not well established. We aimed to determine the rate of PEP in this population and to identify its predictors, especially among immunosuppressive agents. We reviewed all ERCP procedures performed in LT recipients after duct-to-duct biliary anastomoses at 2 high-volume transplant centers. Patients who had undergone sphincterotomy or had a surgically altered pancreaticobiliary anatomy before LT were excluded. Electronic medical records and endoscopy databases were used to obtain clinical, endoscopic, and medication data. A multivariate logistic regression analysis was used to determine predictors of PEP in this cohort. In all, 730 ERCP procedures were performed in 301 patients during the study period with an observed PEP rate of 3% (22/730). A univariate analysis revealed an increased risk of PEP with index ERCP after LT [odds ratio (OR) = 4.04, 95% confidence interval (CI) = 1.40-11.65] and in cases with difficult biliary cannulation (OR = 2.89, 95% CI = 1.10-7.65), whereas prednisone use was found to have a protective effect in both univariate (OR = 0.34, 95% CI = 0.14-0.84) and multivariate analyses (OR = 0.22, 95% CI = 0.09-0.57) after adjustments for difficult biliary cannulation and post-LT index ERCP. This retrospective analysis demonstrates that corticosteroid therapy has a protective role in the development of PEP in LT recipients. Further studies are warranted to confirm our findings. Liver Transpl 19:1354-1360, 2013. © 2013 AASLD.