The results of morphologic examination of the small bowel mucosa of 32 patients with the ischemic disease of the alimentary organs provoked by stenosis of a. iliaca are analyzed. The diagnosis was confirmed angiographically and in the course of operation. Aspiration biopsy of the jejunum was performed by means of Ts. G. Masevich's sound. Chronic intestinal ischemia provokes the development of the atrophic changes in the mucosa with the decrease of its thickness due to the lowering of the height of its villi. The number of the goblet cells is increasing as well as the cell infiltration, the degenerative changes in the epithelium are observed. These alterations correlate with the degree of both the vessel narrowing and collateral circulation.