A method of US hydrocolonoscopy with the use of multicomponent contrast medium has been applied to examine 76 patients with tumors of the straight intestine and segmented one. Cancer has been diagnosed in 56 patients, benign tumors in 19 patients, lymphosarcoma of the blind gut has been revealed in one case. It is stated that a complex US examination of the straight and segmented intestines has a number of additional diagnostic potential in a visualization of the wall thickness, structure, tumor size and in a determination of the lesion length as compared with other radiation methods of observation. The use of survey US examination (USE) of the abdomen, USE with liquid echocontrast diagnostic medium and transrectal observation enable to solve in most cases severe problems in diagnosis and differential diagnosis of cancer of the straight intestine and segmented one.