Preoperative neoadjuvant chemotherapy for rectal cancer is usually done 2~3 times, and some patients need to do 4~6 times. Neoadjuvant chemotherapy for rectal cancer is mainly applied to patients with middle or late stage. Since the tumor lesions of rectal cancer are large and radical surgery is difficult, the tumor can be shrunk by preoperative neoadjuvant chemotherapy, so that rectal cancer patients with late stage can get the chance of radical surgery and the overall survival rate of patients can be improved. Generally, the effect can be evaluated after 2~3 cycles of preoperative chemotherapy, and at the same time, surgeons are invited to consult to evaluate whether radical surgery can be done; if radical surgery is possible, radical surgical resection of rectal cancer will be given as early as possible. If radical surgery is possible, then radical surgery for rectal cancer should be given as early as possible. If radical surgery is still not possible after 2~3 cycles, it is recommended to continue neoadjuvant chemotherapy for a total of 4~6 cycles. Patients are advised to follow the doctor’s instructions and actively treat the disease to prolong the survival period.