Gastric wall thickness (body-antrum) was blind measured prospectively by real-time ultrasound in 58 patients (30 with gastric cancer and 28 healthy) who had previously undergone endoscopy. Gastric wall thickness on the average measured 15.933 +/- 4.471 mm in the neoplastic patients and 5.107 +/- 1.100 mm in the normal subjects. Seven millimeters was the highest value found in the normal subjects (4 cases) and the minimum value found in the neoplastic patients (1 case). Knowing the normal gastric wall thickness value on a standard ultrasound examination of the upper abdomen is useful, as ultrasound is often performed as a screening or first-step procedure, in order to address the patients with higher values toward more specific techniques.