The roentgenograms of 30 adults with well documented celiac sprue demonstrated a remarkably high incidence of abnormalities in the duodenum.These changes consisted of thickened mucosal folds, a decreased number and asymmetric distribution of folds, and a varying degree of duodenal dilatation.The conclusion is reached that these duodenal changes are a distinct roentgenographic manifestation of this entity and, therefore, may be of aid in differentiating it from other disease processes affecting the small bowel.