Abstract: OBJECTIVE To establish the prediction model for postoperative incision infection in the patients with colorectal cancer. METHODS Totally 398 patients with colorectal cancer who were treated in the Affiliated Hospital of Chengde Medical College from Mar 2020 to Oct 2022 were enrolled in the study and were divided into the infection group with 34 cases and the no incision infection group with 364 cases according to the status of incision infection. The distribution of pathogens isolated to the colorectal cancer patients with postoperative incision infection was observed. The risk factors for the postoperative incision infection were concluded, the prediction model was established, and the predictive value of the prediction model was analyzed by means of receiver operating characteristic (ROC) curves. RESULTS Of the 398 patients with colorectal cancer, 34 were complicated with postoperative incision infection, with the infection rate 8.54%. Totally 41 strains of pathogens were isolated, 31 (75.61%) of which were gram-negative bacteria. The result of multivariate logistic analysis showed that body mass index (BMI) no less than 24 kg/m², operation duration no less than 3 hours and hypoproteinemia were the risk factors for the postoperative incision infection in the patients with colorectal cancer(P＜0.05).The above indexes were brought into the risk factor model: Logit(P)=-8.452+0.656×BMI≥24 kg/m²+0.823×operation duration ≥3 h+0.683×hypoproteinemia . ROC curve analysis showed that when Logit(P) was more than 6.45, the area under curve (AUC) was 0.905, with the sensitivity 87.72%, the specificity 85.62%. CONCLUSION The incidence of postoperative incision infection is high among the patients with colorectal cancer. The gram-negative bacteria are dominant among the pathogens, there are a variety of factors for the infection. The prediction model has high value in prediction of the postoperative incision infection in the patients with colorectal cancer.