The authors analysed the medical records of 30 patients with congenital cystic disease of the liver treated in this hospital and with a review of the article some problems of diagnosis and treatment are discussed. B-altrasonic scaner (B-US), computerized tomographic scanning and magnetic resonance imaging appeared to be most helpful in diagnosing and treating this disease. After comparing different treatments, such as aspiration .alcohol sclerotherapy, fenetration, cyst resection and partial hepatectomy, the arthors state the best results could be achieved by alcohol sclerotherapy under B-US guidence (6 cases) or fenestration (15 cases) with no postoperative complication. Malignant change was found in one patient of this group.