Gastrofiberscopy as well as roentgenologic examination of stomach, is now considered to be one of the indispensable diagnostic methods of gastric diseases. In general it is agreed that the roentgenologic examination is convenient for observation of shape, contour, motor function and gross lesions of stomach while gastrofiberscopy is especially valueable in detection of mucosal changes or small lesions of stomach. For evaluation of gastrofiberscopy in the diagnosis of various gastric diseases, the diagnostic accuracy of gastrofiberscopy was studied in 964 cases who underwent the fiberscopic examination in SNUH during the period from March 1, 1968 till April 30, 1971.