It is normal for the colon to have an s-shape at the end, because the end of the colon has an s-shape, so it is called the sigmoid colon, which is part of the colon. The normal shape of the colon is a “B”, or the English letter “S”; the form is curved, so it is named the sigmoid colon, a part of the colon; the end part of the colon that presents the S shape is called the sigmoid colon, which usually curves backward on the right side of the human pelvis, and bends downward in the middle position, reaching directly to the rectum. The sigmoid colon is usually curved backward in the right side of the human pelvis, and it bends downward in the middle position and reaches the rectum directly, with a specific length of about 35~40cm. The main function of the sigmoid colon is to transport gas waste and gastrointestinal excretions to the rectum and anus and other organs and tissues; the upper bowed part of the sigmoid colon is used for storing gas to avoid incontinence when the human body has an exhaust phenomenon. Normally, we should pay attention to drink more water, eat more fresh fruits and vegetables and coarse grains; keep a happy mood and regular life, develop the habit of regular defecation, and appropriately increase the amount of exercise, such as physical symptoms, should go to the hospital in a timely manner, consult the physician’s guidance.