The value of ultrasonography and UGAB for diagnosing chest wall tumors was investigated in 21 patients of whom 13 had metastatic and eight benign disease. Chest wall tumor showed a hypoechoic mass with tapered edges. The margin between the tumor and lung was curved and smooth in all cases. Movement of the tumor during breathing was synchronized with that of the chest wall. We believe that the ultrasonography is of value in identifying tumors that are localized to the chest wall by examination of their margin and movement with respiration, in addition to their shape. Using UGAB, we were able to diagnose correctly all eight metastatic tumors and two of four benign tumors. UGAB is a safe and simple procedure for diagnosing chest wall tumors.