Male left abdominal vague pain on the one hand may be related to diseases of the digestive system, urinary system and reproductive system, on the other hand extrusion, collision and other external forces, acting on the left side of the patient’s abdomen will also cause left abdominal vague pain. If the patient cannot be relieved after rest, he should go to the hospital in time to clarify the cause: a. Genitourinary system diseases: 1. Prostatitis: prostatitis is often caused by retrograde infection of pathogens, mainly Staphylococcus spp. The pain is mainly manifested as local perineal distension and pain, some patients have mild symptoms, if it is a left sperm vesicle attack, it may be manifested as left abdominal hidden pain; 4, other diseases: cystitis, kidney stone shedding complicating ureteral stones and other diseases may cause vague pain in the abdomen and lower abdomen of patients, radiating to the left abdomen causing pain. Second, digestive system diseases: 1, pancreatitis: patients with chronic pancreatitis mainly have pain in the left upper abdomen, accompanied by epigastric fullness, nausea, vomiting and other symptoms, while the left abdomen may be affected, manifested as vague pain; 2, ulcerative colitis: mostly manifested as pain in the left lower abdomen or lower abdomen, the symptoms of pain may gradually develop, from vague pain to obvious pain, and finally full abdominal pain, while often accompanied by The pain may be relieved after defecation. It may also be accompanied by abdominal distension, loss of appetite, nausea and other symptoms; 3. Other diseases: colon polyps, reflux gastritis, irritable bowel syndrome and other intestinal diseases often manifest as abdominal pain in different parts of the body, which may cause vague pain in the left abdomen of patients.