PURPOSE: Clostridium difficile (C. difficile)-associated colitis, a known complication of colon and rectal surgery, can increase perioperative morbidity and mortality, leading to increased hospital stay and costs. Several contributing factors, including advanced age, mechanical bowel preparation, and antibiotics, have been implicated in this condition. The purpose of this study was to determine the clinical features of and factors responsible for C. difficile-associated colitis after colorectal cancer surgery. METHODS: The medical records of patients who had undergone elective resection for colorectal cancer from January 2008 to April 2010 were reviewed. Cases that involved procedures such as transanal excision, stoma creation, or emergency operation were excluded from the analysis. RESULTS: Resection with primary anastomosis was performed in 219 patients with colorectal cancer. The rate of postoperative C. difficile-associated colitis was 6.8% in the entire study population. Preoperative metallic stent insertion (P = 0.017) and aged sixty and older (> or = 60, P = 0.025) were identified as risk factors for postoperative C. difficile-associated colitis. There were no significant differences in variables such as preoperative oral non-absorbable antibiotics, site of operation, operation procedure, and duration of prophylactic antibiotics. CONCLUSION: Among the potential causative factors of postoperative C. difficile-associated colitis, preoperative metallic stent insertion and aged sixty and older were identified as risk factors on the basis of our data. Strategies to prevent C. difficile infection should be carried out in patients who have undergone preoperative insertion of a metallic stent and are aged sixty and older years.