Hidden pain in the left abdomen is most commonly caused by digestive system diseases, urinary system diseases, etc. The time of pain varies from person to person, and it is difficult to judge by the time of attack. 1. Digestive system diseases: If the diet is not clean, infected with Helicobacter pylori or eat irritating food, it can cause gastritis, gastroenteritis, gastric ulcer, duodenal ulcer and other diseases, which can cause hidden pain in the left abdomen, so you need to go to the hospital to do a gastroscopy and breath test and other tests to make a clear diagnosis. 2. Urological diseases: if you drink less water, do not pay attention to personal hygiene, diet combined with irrational, etc., may cause urinary tract inflammation and stone occurrence, resulting in left abdominal pain, it is recommended to improve the ultrasound of the urinary tract as well as urine routine examination to clarify the diagnosis. It is recommended to go to gastroenterology and urology department for further examination, and follow the doctor’s instructions after clarifying the cause of the disease.