Feeling stomach acid in the morning may be caused by physiological factors such as smoking and drinking, irregular diet, and pathological factors such as chronic gastritis and gastric ulcer. 1. Physiological factors: There are many bad habits in daily life, such as smoking and drinking, eating spicy and stimulating food, irregular diet, irregular work and rest, etc., which stimulate the gastrointestinal mucosa and lead to the feeling of stomach acidity. 2. Pathologic factors: (1) Chronic gastritis: gastric acid secretion and food can not be properly transported to the intestine, resulting in feeling stomach acid in the early morning, and possibly vomiting. (2) Gastric ulcer: If you have a gastric ulcer, it will put the gastrointestinal mucosa in an unhealthy state, resulting in a disorder of gastric acid secretion. The gastric acid secreted at night cannot be discharged in time, resulting in the condition of feeling stomach acid in the morning. It is recommended to go to the hospital for diagnosis and treatment in time when the symptom of feeling stomach acid in the morning occurs. In order to avoid untimely treatment, the condition will be aggravated and other complications will be induced, which is not conducive to the recovery of the disease.