Twenty patients with symtomatic congenital cysts in the liver, kidney, thyroid, and lower neck underwent, ultrasound guided percutaneous aspiration through a drainage catheter with temporary instillation of 95% ethanol into the cyst. Our procedure was based on the method as described by Bean and Rodan(16) in 1985. Additionaly, two othe steps were odded to prevent the dilutional effect of residual cyst fluid. One was the preliminary washing of the cyst with alcohol. The other was to treat with 30% replacement of alcohol every 10 minutes during the treatment secession. Minor complications of transient temperature elevation and haziness occurred, butj no major complications were encountered. After the alcohol treatment follow up examinations were performed with computed tomography or ultrasonography at 6 weeks. 6 months, 9 months and 15 months. Although there was diminished size, recurrence was noted in 6 of twenty patients(30%) at 6 weeks and one of twenty patients(5%) at 6 mont s. There was no recurrence at 0 months and 15 months. The results indicated that percutaneous aspiration and alcohol sclerotherapy are safe and effective therapy for symptomatic congenital cysts.