Objective To summarize the clinical characteristics of ischemic colitis (IC) between the elderly and young/middle-aged patients. Methods Clinical data of 200 IC patients with definite diagnosis from June 2010 to December 2016 in our department were collected and retrospectively analyzed. The patients were divided into young/middle-aged group (<60 years old, n=78) and elderly group (≥60 years, n=122). The baseline data, clinical manifestations, laboratory examination results, endoscopic findings, clinical course and outcomes after treatment were analyzed and compared between the 2 groups. SPSS statistics 13.0 was used to perform the statistical analysis. Student’s t test or Chi-square test was employed for comparison between the 2 groups based on different data types. Results When compared with the elderly group, the young/middle-aged group took obviously higher ratios of the subjects with fatty liver and histories of constipation and abdominal operation, while notably lower ratios of hypertension and coronary heart disease (P＜0.05), and remarkably lower ratio of nausea and vomiting (P＜0.01). The levels of platelet (PLT) and fibrinogen (Fg) were significantly lower, while activated partial prothrombin time (APTT) was obviously longer in the young/middle-aged group than in the elderly group (P＜0.05). The endoscopic findings showed that the bowel lesions in the left colon was remarkably higher in the young/middle-aged group than in the elderly group [92.3% (72/78) vs 73.0% (89/122)], while those in the right colon was opposite [7.7% (6/78) vs 27.0% (33/122),P＜0.01]. There was no significant difference between the 2 groups in mucosal congestion and edema, scattered erosion, ulcer and bleeding, and ratio of intestinal stricture (P>0.05). The percentage of completely healed mucosa was 96.2% (75/78) in the young/middle-aged group, and was 91.0% (111/122) in the elderly group (P=0.162). Conclusion The major causes of IC are intestinal factors for young/middle-aged patients, while vascular factors for the elderly. Blood hypercoagulability is common in elderly IC patients.