Stomach pain after hunger may be caused by physiological reasons, gastritis, duodenal ulcer and other reasons. 1. Physiological reasons: when hungry, it will easily lead to an increase in gastric acid, which stimulates the gastric vagus nerve and causes spasmodic pain in the smooth muscle of the stomach. 2. Gastritis: If the patient usually has irregular diet and overeating, it may lead to gastritis, which will cause increased secretion of gastric acid and stomach pain when he is hungry, and is accompanied by symptoms such as acidity and hiccups. 3. Duodenal ulcer: If the patient suffers from duodenal ulcer, it will easily lead to gastric mucous membrane damage, after hunger will prompt an increase in gastric acid secretion, gastric acid flow into the duodenum to stimulate the ulcer wounds, causing localized pain, burning sensation. When you feel stomach pain after hunger, there may also be other reasons, such as gastric ulcer, reflux esophagitis, etc., you should immediately go to the hospital, clear the cause of the disease, and then follow the doctor’s instructions, so as not to delay the condition.