Postoperative diarrhea treatment of rectal cancer has the following main points: 1. Clear cause and symptomatic treatment: if diarrhea occurs after rectal cancer surgery or during chemotherapy, patients or their family members should report to the doctor in charge first, and then carry out relevant examination or symptomatic treatment for the patient’s condition to make the cause clear, and then they can use some relevant medicines, such as bacterial dysbiosis which is generally a non-bacterial infection, and the use of antimicrobials is ineffective at this time, and the diarrhea with dysbiosis can be changed to some anti-bacterial drugs. Diet and physical and mental adjustment: Post-operative rectal cancer patients’ diet should follow the instructions of medical care, regular and quantitative, small meals, gradual, high protein, high vitamin, low-fat and low-salt diet is the main, eat less or not eat spicy and pickled food, too cold, too hot, gas-producing food should not be eaten, which is easy to cause diarrhea, and sensitive people should not consume dairy products. People who are more sensitive to dairy products can not eat dairy products; 3, face reality and adjust mentality: after rectal cancer surgery, patients must face reality and adjust their mentality, keep optimistic mood, participate in some useful sports activities, and do anal lifting exercise frequently to help recovery and help health; 4, wash the anus and perianal skin timely: frequent diarrhea is easy to cause infection of the perianal skin and the anus, which will lead to eczema-like skin changes, wash the anus after stool timely. Changes, timely cleaning of the anus and perianal skin after the stool can protect the skin, not easy to appear further problems.