Men’s left lower abdominal pain may be caused by ureteral stones, autonomic dysfunction, ulcerative colitis, acute enteritis and other causes, the specific causes still need to go to the hospital to determine the examination. 1. Ureteral stones: ureteral stones are usually caused by metabolic abnormalities, improper diet, etc. When ureteral stones occur on the left side, the patient’s left side of the lower abdomen will be pain, some patients will also have hematuria, painful urination, urinary frequency, nausea and other symptoms. 2. Autonomic dysfunction: autonomic dysfunction is mostly caused by heredity, long-term mental stress, infection and other factors, the patient’s gastrointestinal nerve symptoms, such as stomach pain, vomiting, gastric distension, diarrhea, etc., the patient will also have chest tightness, panic, insomnia, numbness of the limbs and other symptoms. 3. Ulcerative colitis: ulcerative colitis is generally caused by intestinal microecology, environment, immune imbalance and other factors, the patient’s pain is generally mild to moderate pain, mostly in the left lower abdomen, and accompanied by diarrhea, abdominal distension, fever, fatigue and other symptoms. 4. Acute enteritis: acute enteritis is generally caused by pathogenic microbial infections, eating cold and other irritating food, dietary impurity, etc., the patient’s main symptoms manifested as abdominal pain, diarrhea, nausea, vomiting, etc., the condition is too serious will also appear shock. If the left side of the lower abdomen hidden pain, should be timely to the hospital for medical treatment, after diagnosis, follow the doctor’s instructions for treatment.