Levy and Granmark had introduced double contrast study in 1896 for the first time. Since Daval and Beclere had human experiment of double contrast air study, so many methods for diagnosis of ge.stric diseases are discovered and improved. 'Aiain valuable purpcses for double contrast study of stomach and duodenum are early diagncsis of stomach cBilcer and differectial diagncsis of ulcer forming malignancy frcm benigncy. In ="'d ticn to t4ese, differentiation of gastroauo"e.al defects, intrin-ic or extrins!c, is also v'orthwlii!e by tl;e metho3 of doub!e cc,ntrast air study of stomach and duodenum. Hvpotonic duodenography is exclusive of misinterpretation of duocenal non lesion in conventi,.nal barium study, as it attributes in cor firmation of nature, extention of lesion, and differer..iation betv;een intrinsic or extrinsic, cr duodenal or papillary lesion in origin, Hypotonic 3uodenogrzphy is helpful in carly diagnosis of disease and avoid misleading unneccessary fv.rther study or explorat- ory laparotomy.