Objective:To investigate the effects of different chemotherapy dose intensity on the short-term efficacy and adverse reactions of patients with advanced colon cancer.Methods:A real-world database of patients with advanced colon cancer in Wangjing Hospital of China Academy of Chinese Medical Sciences and China-Japan Friendship Hospital from January 2017 to December 2020 was established, including 105 patients treated with the same chemotherapy regimen for two consecutive cycles. The patients were grouped according to the average relative dose intensity (ARDI) of chemotherapy, and the population differences, treatment regimens, short-term efficacy and adverse reactions of different chemotherapy dose intensities were evaluated. The receiver operating characteristic (ROC) curve was used to analyze the predictive value of ARDI for short-term efficacy.Results:There were 31 patients in the high dose intensity group (ARDI≥80%) , 34 patients in the medium dose intensity group (80%0.05) . ROC curve analysis found that the area under the curve predicting objective response was 0.70, the sensitivity was 92.30%, and the specificity was 52.10% when the chemotherapy ARDI threshold was 64%. Conclusion:In the real world, colon cancer patients receiving high dose intensive chemotherapy have better objective response rate, and tumor markers decreased significantly. The baseline status of colon cancer patients receiving low dose intensive chemotherapy is poor, but there is no statistically significant difference in disease control rate between patients receiving low dose intensive chemotherapy and patients receiving high dose intensive chemotherapy, and the adverse reactions are controllable.