Left abdominal pain in the elderly is considered to be caused by gastritis, intestinal obstruction, stomach cancer and pancreatic cancer. It can be treated by applying drugs and surgery under the guidance of doctors. 1. Gastritis: usually caused by bad dietary habits, Helicobacter pylori infection and bile reflux, often accompanied by belching (hiccups), nausea, abdominal discomfort, bloating and loss of appetite and other symptoms. Under the guidance of the doctor, it can be treated by applying omeprazole, lansoprazole and other drugs. 2. Intestinal obstruction: usually caused by intestinal torsion, roundworm obstruction, internal foreign body, intussusception, foreign body or fecal mass blockage, toxin stimulation, nerve inhibition and other factors. It is often accompanied by abdominal pain, vomiting, abdominal distension and cessation of defecation. Generally, it can be treated by intravenous infusion to correct water and electrolyte disorders and acid-base imbalance or surgery. 3. Gastric cancer: usually caused by Helicobacter pylori infection, poor diet, mental health, smoking, alcohol and heredity, etc. It is often accompanied by abdominal distension and pain, nausea, loss of appetite, belching (hiccups), acid reflux, black stools and other uncomfortable symptoms. Under the guidance of doctors, it can be relieved by applying trastuzumab, omeprazole and other drugs. 4. Pancreatic cancer: It is usually caused by high-fat diet, excessive body mass index long-term smoking, advanced age, concomitant diabetes or chronic pancreatitis. It is characterized by jaundice, nausea, vomiting, abdominal discomfort and diabetes. Warm reminder: when the body appears abnormal symptoms, must be timely medical treatment, so as not to delay the condition, affecting the treatment.