Choledochal cyst is a rare congenital anomaly of the biliary system, presenting in infancy. Two cases of choledochal cyst (one infected) with grossly deranged liver function tests and associated biliary atresia, which were successfully managed pre-operatively by sonoguided percutaneous choledochalcystostomy, are reported here. The use of this technique in the treatment of patients such as these is proposed.