OBJECTIVE To investigate the risk factors and the prevention management of anastomotic leak in patients with Crohn disease undergoing bowel resections. METHODS Clinical data of 91 patients with Crohn disease undergoing intestinal resection from 1990 to 2010 were analyzed retrospectively. Logistic regression analysis was used to assess the risk factors of anastomotic leak. RESULTS A total of 120 intestinal anastomosis were performed in 91 patients, and anastomosis leak occurred in 14 patients (11.7%). Univariate analysis showed that operative timing (emergency or elective surgery), anastomosis type (side-to-side or end to end and end-to-side), operative time (≥3 h or <3 h), methods of anastomosis (handsewn or stapled) were the risk factors for anastomotic leak (P<0.05). Multivariate analysis revealed that emergency surgery (OR=3.891, 95%CI:1.332-13.692), end to end and end-to-side anastomosis (OR=3.236, 95%CI:1.165-11.950), handsewn anastomosis (OR=5.715, 95%CI:1.454-17.328) were independent risk factors of anastomotic leak. CONCLUSION Avoiding emergency operation, use of side to side anastomosis, and application of stapling may lower the incidence of postoperative anastomotic leak in patients with Crohn disease undergoing bowel resections.