Objective:To explore the influencing factors of unqualified bowel preparation before colonoscopy in patients with chronic constipation, in order to propose corresponding countermeasures.Methods:Using the convenient sampling method, a total of 146 patients with chronic constipation who underwent colonoscopy in Gastroenterology Department of Shanxi Provincial People's Hospital from February 2018 to April 2020 were selected as the research subjects, and the unqualified conditions of them were counted. Single factor analysis and multivariate Logistic regression analysis were used to screen out the influencing factors of unqualified intestinal preparation and propose the corresponding nursing countermeasures.Results:Among 146 patients with chronic constipation, 15 cases (10.27%) were unqualified in intestinal preparation before colonoscopy, including 7 cases (4.79%) in left colon, 5 cases (3.42%) in transverse colon and 3 cases (2.05%) in right colon. Univariate analysis showed that there were statistically significant differences in intestinal preparation qualification among patients of different ages, whether they had insufficient activity during medication, whether they had a history of diabetes, whether they had a history of abdominal or pelvic surgery and different courses of chronic constipation ( P<0.05). Multivariate Logistic regression analysis showed that age older than 60 years, insufficient activity during medication and history of diabetes were independent risk factors for unqualified bowel preparation before colonoscopy in patients with chronic constipation ( P<0.05) . Conclusions:Old age, insufficient activity during medication and history of diabetes are all risk factors for unqualified bowel preparation before colonoscopy in patients with chronic constipation. And targeted nursing programs should be developed according to the actual conditions of patients to increase the pass rate of bowel preparation.