Colorectal cancer screening includes both non-invasive and invasive methods. Non-invasive tests are usually used for primary screening and mainly include questionnaire assessment, fecal occult blood test and fecal DNA testing. Invasive tests mainly include endoscopic examination. 1. Non-invasive tests: The screening population can be differentiated from the high-risk group by detailed and specific questionnaires on high-risk factors and scores from the Asia-Pacific Colorectal Tumor Screening Scoring System. Stool tests are highly accepted and sensitive and can be used for primary screening, including fecal occult blood test and multi-target stool DNA test. 2. Invasive tests: including endoscopy, etc. Colonoscopy or sigmoidoscopy + pathological biopsy is currently recognized as the best method to diagnose colorectal cancer. The sensitivity and accuracy of endoscopy are higher than that of non-invasive examination, but it also has the risk of bowel perforation and bleeding. Colorectal cancer is one of the common malignant tumors, and its prognosis is closely related to early diagnosis. Therefore, it is recommended that patients with high risk factors for colorectal cancer should go to the hospital regularly for relevant examinations, and find out the lesions and treat them as soon as possible so as to avoid delaying their conditions.