The authors evaluated ultrasonographic findings of surgically or pathologically proven anterior abdominal wall lesion in 17 cases. The reuslts were follows: 1. Ultrasonography is an accurate, convenient and noninvasive method to detect and determine the extent of anterior abdominal wall lesion. 2. Peritoneal fascia interface is an important landmark in differenciation between intraperitoneal and abdominal wall lesion. 3. Sonographic differenclation of abscess and hematoma from tumor was impossible.