Aim/Materials and Methods Between January 2000 and June 2007, 3,548 endoscopic retrograde cholangiopancreatography (ERCP) were performed for extrahepatic cholestasis, cholangitis, and choledocholithiasis. The results of ERCPs were evaluated retrospectively and examined carefully to investigate the management and endoscopic therapy of biliary parasites. Results Of the 3,548 patients who underwent ERCP, 24 (0.66%) were found to have biliary parasitosis. The mean age of the biliary parasitosis patients (16 women) was 48.6 (15-77) years. Of these 24 cases, 16 patients had hydatid cystic disease (eight with partial obstruction of the biliary tract, and eight with ruptured cysts), four patients had Fasciola hepatica, and four patients had Ascaris lumbricoides infestation. Endoscopic sphincterotomy was performed, after which the choledochus was examined carefully by balloon catheter and basket procedure. Conclusion The ERCP procedure is very useful in the therapy of biliary parasitic infestations.