Type IVa choledochal cysts with cylindrical dilatation of the intrahepatic ducts constitute a relatively less recognized variety of choledochal cysts, and differ from cystic dilatation of intrahepatic ducts in their clinical manifestations and response to treatment. Five patients with type IVa choledochal cysts and cylindrical dilatation of major intrahepatic ducts who underwent cyst excision and Roux-en-Y hepaticojejunostomy are reported. The duration of symptoms was less than 1 year in all patients. Palpable abdominal mass and abdominal pain were present in 3 patients. The traid of jaundice, abdominal pain and mass was present in only 1 patient. The intrahepatic dilatation regressed after excision of the extrahepatic cyst just below the hilum of the liver. The surgical technique is described and the need for excision of the cyst is emphasized.