Colorectal cancer includes colon cancer and rectal cancer. In recent years, with the rapid increase in incidence, colorectal cancer has become one of the highest incidence diseases among gastrointestinal tumors. Among them, the urban growth rate is rapid, rising by nearly one-third compared to the 1990s, and colorectal cancer has become second only to gastric cancer among gastrointestinal tumors. What is of more concern is that this cancer, which used to belong to the middle-aged and elderly, has quietly “targeted” the young. Research shows that the increase of high fat, high protein and low fiber food intake and the decrease of exercise are the main factors of the rapid increase of gastrointestinal tract malignant tumors such as intestinal cancer. Young people suffering from colorectal cancer often have the following characteristics: First, early detection is rare. Young people are not highly alert, and many of them go to the hospital only when their symptoms last for a long time, and are already in the middle and late stages when diagnosed. Secondly, the malignancy is high. Due to the vigorous metabolism and fast division of cancer cells, the malignant degree is often higher than that of middle and old people. Among the diagnosed colorectal cancer in young people, poor differentiation, high incidence of distant metastasis and regional lymph node metastasis directly affect the treatment effect. Thirdly, there are many missed diagnoses. Generally, from the time young people go to the hospital for treatment to the time they are diagnosed, the whole time is about 5-15 months, and most of them are diagnosed as hemorrhoids and enteritis at the early stage, so the rate of missed diagnosis is as high as 70%. Fourth, the surgical excision rate is low and the prognosis is poor. As most patients are already in the middle and late stage when diagnosed, the tumor has metastasized or invaded the surrounding tissues and organs, the radicality of surgery is poor, and sometimes the tumor cannot even be removed. It should be emphasized that colorectal cancer is not a sudden lesion on the intestinal mucosa, but develops through the sequence of “normal mucosa – adenoma – cancer”. It is found that more than 80% of colorectal cancers are transformed from colorectal adenoma, thus precancerous lesions must be treated timely and reasonably, i.e. early detection and early treatment. The 5-year survival rate of early colorectal cancer is 90% after surgery, but less than 10% in late stage. As colorectal cancer is insidious, early stage is often only positive fecal occult blood, no obvious discomfort symptoms, so young people with family history of bowel cancer or colon polyps, when symptoms such as change in stool habit, alternating constipation and diarrhea, unexplained blood in stool or black, tar-like stool, abdominal pain and abdominal lumps, wasting, weakness, anemia, etc. occur, they should immediately go to the gastroenterology department for fecal occult blood test and or colonoscopy. Do not delay the diagnosis because of “young” paralysis.