Ultrasonography is very important in the diagnosis of intraabdominal abscess and it has high accuracy. Authoranalyzed the ultrasonographic findings of 94 patients with intraabdominal abscess and the results were as follows.1. In tottal 94 cases, the intraperitoneal abscess was 51(RLQ abscess in 18 cases), the retroperitoneal abscess 11(posterior pararenal in 6 cases), and the visceral abscess 32 cases(liver abscess in 21 cases). 2. The causes ofintraabdominal abscess were recovered in 75 patients, complication of intraabdominal operation was 26, acuteappendicities was 13, biliary tract disease was 10 cases, etc. 3. The shape of the lesion was round or oval inmost cases (70.5%). The subphrenic and subhepatic abscess showed mainly crescenteric shape, The abscess in theretroperitoneal and in the paracolic gutter showed elliptical shape. 4. The size of the lesion was under 5cm indiameter in 47.3%. Large lesions over 10cm in diameter were noted in the subphrenic and retroperitoneal space. 5.Most frequent finding of echo pattern was cystic lesion with internal echogencity(67%). Abscess wall and posteriorreinforcement were noted in about half of the cases.