Tumor indicators can be checked during bowel cancer screening, with emphasis on carcinoembryonic antigen examination. If the index of carcinoembryonic antigen is elevated, it indicates that the patient may have bowel cancer, and further examination such as abdominal CT or colonoscopy is needed. In addition, for those who have family history of hereditary disease, regular colonoscopy is recommended because colonoscopy is the main examination method to detect lesions inside the intestines of patients, and for early stage of intestinal cancer, if the lesions inside the intestines are relatively small, colonoscopy can also detect them. If the patient can be diagnosed with bowel cancer at an early stage, surgery can be performed in time, and after surgery, the overall effect will be very good if supplemented with other treatment methods. There are also some new screening methods such as fecal DNA test to screen for bowel cancer.