Abstract: At present, the treatment of colorectal cancer has changed from the inherent treatment mode of "surgery as the main therapy, radiotherapy and chemotherapy as adjuvant therapy" to the precise and individualized treatment concept, and immunotherapy has been paid more and more attention. However, not all the patients respond to immunocheckpoint inhibitors. Therefore, predicting the possibility of treatment response will help to screen the patients who can benefit. Many studies have shown that tumor mutation load has a positive correlation with the efficacy of immunosuppressive checkpoint inhibitors, and it can become an independent biomarker of immunotherapy. In this study, the prediction value and application status of tumor mutation load in immunotherapy of patients with colorectal cancer were reviewed.