OBJECTIVE: To investigate knowledge and fear of colorectal cancer (CRC) risk in inflammatory bowel disease (IBD) patients. METHODS: A 12-item self-administered questionnaire, developed after a careful literature review, was administered to all consecutive IBD patients treated with infliximab who were followed up at Nancy University Hospital (Vandoeuvre-lès-Nancy, France) between February and May 2012. RESULTS: Altogether 100 patients including 72 with Crohn's disease (CD) were included. Only 7.0% of patients spontaneously mentioned CRC risk as a main feature of IBD and 37.0% as a potential IBD complication. CRC was the most feared complication by 26 patients [ulcerative colitis (UC) 46.4% vs CD 18.1%, P < 0.01]. Two-thirds of patients knew that IBD increases CRC risk (UC 81.9% vs CD 57.1%, P = 0.02). Their main source of information was their gastroenterologist (52.0%). On the best screening method for CRC, 86.0% of the respondents mentioned colonoscopy. Only 32.0% of patients knew that it has to be performed 10 years after diagnosis. In case of dysplasia, 51.0% of the patients would not undergo colectomy (CD 59.7% vs UC 28.6%, P < 0.01), mainly due to the fear of having ostomy bags. Only one-quarter of UC patients were aware of the chemopreventive effect of 5-aminosalicylates on CRC risk. CONCLUSIONS: Two-thirds of IBD patients are aware of the risk of CRC. UC patients have a better knowledge of this risk and are more afraid of this complication. Our results underscore the need for therapeutic education about CRC in IBD patients.