Left upper abdominal pain may be related to cardiovascular diseases, stomach diseases, spleen diseases, pancreatic diseases and so on. 1. Cardiovascular diseases: angina pectoris, coronary heart disease and other cardiovascular diseases, not all manifested as cardiac discomfort, the symptoms of atypical people often just feel the discomfort of epigastric distension, the need for cardiac enzymes, electrocardiograms, coronary CTA and other tests to clarify the diagnosis. 2. Gastric diseases: patients with gastritis, gastric ulcer and other gastric diseases can also be accompanied by vague pain in the left upper abdomen, acid reflux, belching and other symptoms, gastroscopy can help to clarify the cause of the disease. 3. Spleen diseases: patients with spleen tumors, spleen cysts and other diseases may also lead to bloating and pain in the left upper abdomen, and the bloating and abdominal pain may be further aggravated with the increase in the size of tumors or cysts. 4. Pancreatic diseases: such as pancreatic tumors, pancreatic inflammation, pancreatic cancer and other lesions, it is also easy to cause pain in the upper left abdomen. Left upper abdominal pain can also be caused by other reasons, the symptoms continue to be unrelieved, it is recommended to go to the hospital in time to improve the relevant examinations and laboratory tests, targeted treatment.