A very hard abdomen may be related to physiological factors, or it may be caused by acute diffuse peritonitis, intractable constipation, intra-abdominal tumors, and so on. 1. Physiological factors: for example, overeating, resulting in the temporary accumulation of food in the gastrointestinal tract, there may be a very hard abdomen. It may also be due to regular exercise, abdominal muscle development, which may show the abdomen is very hard, these are normal physiological phenomena. 2. Acute diffuse peritonitis: for example, due to acute inflammation induced by perforation of the duodenum, resulting in the gastrointestinal tract of intestinal fluids, gastric fluids seeped into the abdominal cavity, resulting in infection, which may cause a very hard abdomen, clinically known as the “plate-like abdomen” signs. Often accompanied by diffuse abdominal pain. 3. Persistent constipation: If there is persistent constipation, leading to dry and hard stools, resulting in a decrease in the frequency of defecation, defecation difficulties, resulting in a large amount of fecal matter in the intestinal tract, it may cause a very hard abdomen. 4. Intra-abdominal tumor: For example, colon cancer, rectal cancer, stomach cancer, etc., because the tumor occupies the position in the abdominal cavity, it may cause abdominal mass, which is hard and not easy to move. The hardness of the abdomen may be caused by other reasons. After excluding physiological factors, the patient should consult a doctor in time to clarify the causes and then give targeted treatment.