Patients wake up with sour mouth after sleep for the following reasons: 1, because of wounded food, food stagnation in the stomach and stomach, sour smell and other reasons, there will be symptoms of sour mouth. In this case, should pay more attention to their diet, try not to eat food on fire, eat more easily digestible food, diet should be light, more serious can be appropriate to use the elimination of food tablets. 2, poor oral cleaning, gingivitis, there will be gum bleeding, gingival sulcus fluid increased, there will be symptoms of acidity. After paying attention to diet and oral cleaning there are still this symptom, to go to the gastroenterology department to check whether there is gastritis, reflux esophagitis and other digestive tract diseases, usually pay attention to diet and regular rest, avoid staying up late and eating spicy and stimulating food.