Objective To explore the influencing factors for pulmonary infection after radical resection of colon cancer. Methods A cohort study included 56 patients who underwent radical resection of colon cancer in People’s Hospital of Daye City from Oct. 2014 to Oct. 2016 were followed-up prospectively, to observe the occurrence of pulmonary infection, and collectting the related factors for pulmonary infection in addition. Results The clinical data of 53 patients were finalized and the clinical data of these patients were complete. Among them, 13 patients suffered from pulmonary infection after radical resection of colon cancer, and 40 patients had no obvious exacerbation and no complicated pulmonary infection. Results of logistic regression showed that, value of forced expiratory volume in1 second/forced vital capacity (OR=1.174, P=0.033), operative time (OR=1.638, P=0.012), levels of postoperative copeptin (OR=1.328, P=0.032), and procalcitonin (OR=1.465, P=0.042) were risk factors for pulmonary infection after radical resection of colon cancer. Receiver operating characteristic curve (ROC) showed that, operative time was 6.207-hour, postoperative copeptin level was 10.420 pmol/L, and the postoperative procalcitonin level was 3.676 ng/mL, which had the best predictive effect on predicting pulmonary infection after radical resection of colon cancer. Conclusions Value of forced expiratory volume in 1 second/forced vital capacity, operative time, levels of copeptin and procalcitonin after operation are the independent influencing factors for pulmonary infection after radical resection of colon cancer, and it has best prognostic outcome when the operative time is 6.207-hour, postoperative copeptin level is 10.420 pmol/L, and the postoperative procalcitonin level is 3.676 ng/mL.