Rectal finger examination is one of the most important examination methods for anorectal surgeons, which is to enter the rectum by the anus with the right hand wearing gloves and the index finger coated with paraffin oil. First feel the looseness of the anal opening to see if there is any relaxation, any anal stenosis or tension, then enter further to see if any swelling, tumor or hard nodes occur, and then observe whether there is any bleeding or mucus on the finger sleeve. Many diseases can be detected through finger examination, such as polyps, anal papillomas, rectal cancer and other diseases. Except for children and toddlers whose anus is small and the doctor’s finger is not quite suitable, all patients can have anal fingering, which does not cause damage and can detect many diseases that cannot be detected.