Patients with stage II colon cancer, staged as T3N0M0, with deletion of mismatch repair genes, generally do not need postoperative adjuvant chemotherapy after surgery because it is generally believed that this type of patients do not benefit from chemotherapy, and regular review is sufficient. Stage II colon cancer is divided into low-risk, generalized risk and high-risk. Low-risk patients are those with T3N0M0 and mismatch repair gene deletion, and these patients generally do not need postoperative adjuvant chemotherapy, and regular review is sufficient. For general-risk patients with T3N0M0, normal mismatch repair gene and no risk factors, fluorouracil monotherapy is recommended after surgery. Patients with high risk of T3N0M0 or normal mismatch repair gene with high risk factors (high risk factors include T4, poor histological differentiation, vascular infiltration, nerve infiltration, preoperative intestinal obstruction or perforation of the tumor site, and fewer than 12 lymph nodes sent for examination) or T4N0M0 need to be given oxaliplatin plus capecitabine combination chemotherapy regimen. Patients with stage II colon cancer should go to the hospital in time to improve the staging and treatment under the guidance of oncologists.