Background The aim of this study was to compare the success and complications of diagnostic and therapeutic ERCP in children (age <18 years) and adult patients. Methods A retrospective case-controlled study was conducted in which all children undergoing ERCP at two centers (1994-2002) were identified from endoscopy databases and were matched with adult patients for all variables (e.g., indication, procedure complexity) except age. Outcomes with regard to technical success and complications were compared between the adult and the pediatric cohorts. Grade of procedure complexity and procedure-related complications were defined by using established criteria. Results A total of 116 children (mean age 9.3 years, range 1 month to 17 years; median age 8.1 years) and 116 matched adult patients (mean age 56.3 years, range 20-83 years; median age 49.7 years) underwent 163 and 173 ERCP procedures, respectively. According to procedure complexity grade, each group included the same number of patients, grade I, 72 patients; grade II, 12 patients; and grade III, 32 patients. Procedure success rate was 97.5% in children vs. 98% in the adult cohort (p = not significant). The complication rate was not significantly different between children and adult patients (3.4% vs. 2.5%). Most complications were of mild severity and encountered only in patients who underwent grade III procedures, with the exception of a single adult in whom moderate post-sphincterotomy bleeding developed after extraction of a large bile duct stone (grade II complexity). Conclusions When ERCP is performed in children by expert endoscopists, the success rate is high and the complication rate is low, both being comparable with those for ERCP in adult patients.