A vague pain in the stomach when you are hungry may be due to irregular diet, stomach cramps or duodenal ulcer and other diseases. 1. Gastrointestinal dysfunction: Due to irregular diet, indigestion and gastrointestinal dysfunction can be manifested as abdominal pain and bloating. 2. Stomach cramps: Overeating, eating spicy and stimulating food for a long time may induce stomach cramps. As patients with stomach cramps are more sensitive to stomach stimulation, when the stomach completes gastric emptying and produces the feeling of hunger, the subsequent secretion of gastric acid will easily stimulate the stomach and lead to vague pain. 3. duodenal ulcer: duodenal ulcer is generally due to excessive secretion of gastric acid induced, so in the human body under the state of hunger, the stomach will abnormally secrete an excessive amount of gastric acid, stimulating injury to the duodenal mucous membrane, the stomach is connected to the duodenum, the patient will feel the hidden pain in the stomach. The above is only a part of the possibility of stomach pain when you are hungry, it is recommended that the patient go to the hospital as soon as possible for a comprehensive examination, early treatment and recovery.