ObjectiveTo intend to propose a new clinical classification of congenital biliary dilatation (CBD) which is more concise and suitable for diagnosis and treatment, and explore feasibility and reliability of the new classification. MethodsBased on the preoperative imaging data of patients with CBD admitted to the Department of Pediatric Surgery of West China Hospital of Sichuan University, from January 2015 to December 2018, a new classification of CBD was accomplished according to the site of bile duct dilatation lesions, which was named HUAXI CBD classification. The CBD was classified into 4 types: type Ⅰ (distal extra-hepatic bile duct dilatation), type Ⅱ (distal extra-hepatic combined with right and left primary hepatic bile duct dilatation), type Ⅲ (extra-hepatic combined with secondary and above hepatic bile duct dilatation), and type Ⅳ (intra-hepatic bile duct dilatation). Meanwhile, the feasibility and reliability of the HUAXI CBD classification were analyzed. ResultsA total of 300 patients with CBD were included in this study. According to the HUAXI CBD classification method, 240 cases were type Ⅰ, 48 cases were type Ⅱ, 10 cases were type Ⅲ, and 2 cases were type Ⅳ. For type Ⅰ, 236 patients underwent cholecystectomy and Roux-en-Y hepaticojejunostomy and 4 cases were treated non-operatively; For type Ⅱ, 48 patients underwent cholecystectomy, central hepatic duct reconstruction and Roux-en-Y hepaticojejunostomy; For type Ⅲ, 9 patients underwent cholecystectomy and Roux-en-Y hepaticojejunostomy, 5 of which had intrahepatic dilatation confined to part of the liver lobe and underwent partial hepatectomy with intra-hepaticojejunostomy. One case was treated with percutaneous transhepatic cholangial drainage (PTCD) only; two type Ⅳ patients were treated with PTCD only. Patients with type Ⅰ had a normal hepatobiliary function after surgery and a good prognosis; patients with type Ⅱ had good recovery of liver function in 37 cases (77.1%), but 11 cases (22.9%) had postoperative complications during follow-up; patients with type Ⅲ and Ⅳ had high incidence of cholangitis (6/10, 2/2, respectively) and choledocholithiasis (5/10, 2/2, respectively) after surgery, especially those with diffuse intrahepatic dilatation having a poor prognosis, eventually developing cirrhosis and necessitating liver transplantation. ConclusionThe HUAXI CBD classification is consistent with treatment principles, concise and easy to remember, and more suitable for pediatric clinical application, which can effectively assist in the selection of clinical treatment strategies for children with BD.