Most colorectal cancers develop from mucosal lesions to polyps and then from polyps to cancer, and this process takes about 10 years. Colorectal polyps and early colorectal treatment are satisfactory, and the 5-year survival rate of stage I colorectal cancer can reach more than 90%. Therefore, regular checkups, early detection and early treatment are the key aspects of prevention and treatment of colorectal cancer. Generally, people without family history of the disease should have a thorough colorectal examination at the age of 50, preferably colonoscopy, and then review colonoscopy every 5-10 years, during which it is sufficient to go to anorectal specialist once a year for anal fingering and S stool occult blood examination. If someone in the family has colorectal cancer, the first thorough colorectal examination should be done 10 years earlier than the age of onset of the youngest patient in the family, with colonoscopy preferred, and subsequent colonoscopy every 3 to 5 years. Likewise, during this period, we should go to the anorectal specialist once a year for anal finger examination and S stool occult blood examination.