Follow-up observation or single agent fluorouracil-based chemotherapy is recommended for stage II (stage II) colon cancer after surgery if there are no high-risk factors. For those with high risk factors, adjuvant chemotherapy is recommended. However, it still needs to be judged comprehensively according to the actual situation of patients. For patients with stage II colon cancer, adjuvant chemotherapy is recommended if there are high-risk factors such as poor histological differentiation (grade III or V) and normal mismatch repair or microsatellite stability, T4, vascular lymphatic infiltration, preoperative intestinal obstruction/intestinal perforation, insufficient lymph nodes detected in the specimen (<12), neural invasion, positive margins, or inability to determine. If there are no risk factors, follow-up observation or single-agent fluorouracil-based chemotherapy is recommended. Postoperative adjuvant chemotherapy is not recommended if the tumor tissue examines for mismatch repair defects or high levels of microsatellite instability. The need for postoperative adjuvant chemotherapy should be determined by comprehensive consideration of the patient’s condition. Patients with stage II colon cancer should consult the hospital in time and standardize the treatment under the doctor’s guidance to avoid delaying the condition.