Abstract: OBJECTIVE To investigate the related factors of postoperative infection in patients with gastrointestinal tumors and discuss the corresponding solutions, so as to provide references for the clinical prevention of postoperative infection. METHODS According to the standard of admission, 1049 patients with gastrointestinal tumors without distant metastases who underweny surgical operations from Mar. 2012 to Mar.2015 were selected. The variables of relevant factors were selected and retrospectively analyzed, and univariate and multivariate analysis were performed. RESULTS There were 76 cases occurred postoperative infection, with the infection rate of 7.24%. Multivariate logistic analysis showed that the operation time ≥3 h, the preoperative albumin level <30 g/L, the ASA grade <Ⅱ, and the preoperative chemotherapy were the independent risk factors of postoperative infection in patients with gastrointestinal tumors (P<0.05). CONCLUSION Increasing the preoperative body and psychological preparation of patients, improving the management of the operating room staff, increasing coordination between departments, and reducing the surgical time can reduce the incidence of postoperative infection.