Colon cancer t3n0m0 middle differentiation patients with high risk factors need chemotherapy. Clinically, patients with colon cancer t3n0m0 usually belong to stage II colon cancer, and they will have symptoms such as weight loss, blood in stool, anemia, etc. Stage II colon cancer patients with high-risk factors need chemotherapy, which can reduce the possibility of further deterioration of the patient’s condition. Patients with stage II colon cancer can receive chemotherapy drugs such as 5-fluorouracil, capecitabine, oxaliplatin and so on, and the specific chemotherapy program needs to be chosen according to the doctor’s prescription. Some patients will have gastrointestinal reactions such as nausea, vomiting and other adverse reactions such as decrease in white blood cells, platelets and hemoglobin after chemotherapy. Patients with stage II colon cancer are recommended to consult doctor in time and follow doctor’s instruction to carry out chemotherapy, and pay attention to monitoring the adverse reactions during the use of drugs to avoid aggravating the condition.