Biliary tract complications develop in 5-10% of patients undergoing liver transplantation. They should be differentiated from other causes of graft dysfunction. The role of endoscopic retrograde cholangiopancreatography (ERCP) in the diagnosis and treatment of these patients is analyzed in a series of 116 liver transplant patients. Nine patients (7.8%) were suspected to have biliary complications, and only four of them required immediate surgery because of early accidental T-tube removal and biliary tract stricture. The remaining five patients could be satisfactorily diagnosed and managed by ERCP which showed bile casts in the common bile duct in one case, and bile leaks in four cases, all of them being successfully resolved after endoscopic papillotomy. There were no complications related to the procedure. ERCP and endoscopic papillotomy is the technique of choice for diagnosis and treatment of biliary tract complications after liver transplantation.