Preoperative rectal cancer patients need a lot of nutrients due to the growth of tumor, robbing the normal supply of the body, with the increase of tumor, patients will lose weight and generally lose weight; after tumor resection, the weight will generally increase with the restoration of diet, but it is not equal to the fact that all rectal cancer postoperative patients will gain weight in one year after the operation, and the weight gain or loss varies from one person to another. However, it does not mean that all postoperative rectal cancer patients will gain weight within one year after surgery! According to relevant literature, about 40%-50% of patients will have recurrence or metastasis after surgery, among which, a small number of patients will have recurrence and metastasis for more than 5 years, or even more than 10 years. 70% of postoperative recurrences of rectal cancer occur within 2 years after surgery. Distant recurrences are often asymptomatic and are usually detected by postoperative follow-up, so the follow-up strategy recommended by the current guideline is to review every 3-6 months within 2 years after surgery, and every 6 months for 3-5 years after surgery. The items for review generally include rectal fingerprinting, tumor markers, colonoscopy and pelvic CT. rectal fingerprinting can determine the activity of the mass; tumor markers have an accuracy of up to 94% in detecting postoperative recurrence of rectal cancer; and pelvic CT has an even higher detection rate, and it can also determine the location of the tumor, its size, and whether it has metastasis, etc. The location of recurrence is classified into two categories: location, size, and whether there are metastases. The location of rectal cancer recurrence is categorized into central recurrence, anterior recurrence, posterior recurrence and lateral recurrence, among which lateral recurrence has the worst prognosis. Local recurrence often manifests as pain, blood in stool, constipation, fall in perineum, etc. If the tumor invades bladder, ureter, etc., corresponding urinary system and other symptoms will appear. Early recurrence is usually asymptomatic, and if the above symptoms appear, it may be manifested in advanced stage and the prognosis is not so good. Therefore, patients after rectal cancer surgery must emphasize on regular postoperative review, reasonable dietary arrangement, and keeping optimistic and cheerful mind.