Objective To explore the clinical value ofmulti-slice spiral CT (MSCT) to carcinomatous intestinal obstruction of colon.Methods The clinical and MSCT data of 40 patients with carcinomatous intestinal obstruction of colon diagnosed by MSCT were analyzed.Results In the 40 cases,complete intestinal obstruction were in 17 cases,incomplete intestinal obstruction in 23 cases,39 cases were carcinomatous intestinal obstruction of colon confirmed by surgery and pathology,and 1 case was intussusception intestinal obstruction by multiple polyps.The MSCT qualitative analysis of obstruction reason was 97.5％ (39/40),the MSCT diagnostic accuracy of intestinal obstruction was 100.0％ (40/40).The obstruction site was at ascending colon showed in 14 cases,transverse colon in 4 cases,splenic flexure of colon in 2 cases,descending colon in 6 cases,sigmoid colon in 12 cases,both ascending colon and transverse colon in 1 case,colon and small intestine in 1 case.The obstruction site accuracy rate of MSCT was 100.0％ (40/40).Conclusion MSCT has obvious advantages in obstruction existing,obstruction site,obstruction reason to carcinomatous intestinal obstruction of colon,it can offer reliable examination data to clinic.