Sixty three cases (male 32, female 31) of supravesical obstruction were treated with ultrasonically guided subcutaneous nephrostomy at our hospitals from October 1980 to October 1984. Their age ranges from 2 months to 84 years old, and median age was 52 years old. The major causes of ureteral obstruction were extended pelvic malignancies, 45 cases (71%) (gynecological 18, urological 16, gastrocolorectal 7 and others 4), and benign disease 18 cases (29%). Objectives of nephrostomy were classified in 4 categories (drainage, manipulation, irrigation and evaluation), and results of nephrostomy were discussed for each category. No major complications were observed. Only prolonged macrohematuria (over 48 hours) and fever (over 38 degrees C) were observed in 5 cases respectively. Success rate of nephrostomy placement was 97.5% of all cases. With ultrasonography and angiographic technique, percutaneous nephrostomy is an easy, safe and reliable method.