The cause of hemorrhoids is not yet fully understood, but is generally considered to be related to the following factors: (1) the upright state of the human body: because the anorectum is located in the lower part of the trunk, and people are often in an upright position, the anus is low relative to the heart, due to the gravity factor, the anorectal area of the blood flow back to the heart is more difficult, easy to depress into hemorrhoids, and the animal heart is lower than the position of the anus, so far not found There are animals with hemorrhoids. (2) It is related to the lack of valves in the hemorrhoidal veins. The veins in other parts of the body have many valves, which are like valves in the blood vessels that allow blood to flow in one direction only and not back. However, there are no valves in the hemorrhoidal veins in the anal area, and blood tends to stay in the area, leading to local varicose veins and the gradual formation of hemorrhoids. (3) It is related to infectious factors. Inflammatory changes can often be seen in the hemorrhoidal tissue during a slide examination, so some scholars believe that infection and thrombosis of the hemorrhoidal venous plexus is the cause of the formation of hemorrhoids. Inflammation of the intima and perivenous inflammation of the vascular lining causes the walls of the hemorrhoidal plexus to become brittle, thin, varicose, and finally form hemorrhoids. (4) It is associated with constipation and prolonged bowel movements. When a dry hard stool enters the rectal jug abdomen, it exerts a certain pressure on the rectal wall and the upper part of the anal canal. The arteries and veins on the hemorrhoids between the hard stool and the rectum and long tube anal layer are squeezed by the stool, and the venous pressure is low and inelastic, so the blood return is easily obstructed. However, arterial pressure and high and elastic, not easy to be squeezed, blood can still continue to enter the anorectum. The venous reflux is blocked, and the blood that enters will accumulate in the venous plexus of the anorectum, causing the plexus to dilate and become tortuous, gradually forming varicose veins centered on small arteries in the long run, and finally increasing in size to form hemorrhoids. (5) Related to diet. Too little fiber in the diet can lead to constipation, and drinking alcohol and eating spicy and irritating food can also stimulate anorectal congestion and impaired local blood circulation, which over time can lead to the formation of hemorrhoids. (6) It is associated with diseases such as emphysema and chronic bronchitis that increase abdominal pressure. High abdominal pressure can affect the blood return to the anorectal area and aggravate the varicose veins of hemorrhoids. In addition, cirrhosis of the liver and portal vein thrombosis can cause hyperpressure in the portal vein, which directly leads to a rise in pressure in the hemorrhoidal plexus, which is also a factor in the formation and aggravation of hemorrhoids. In addition, the formation of hemorrhoids may also be related to occupation, genetics, age, and gender.