The most common symptom is abdominal discomfort. The discomfort is usually a painful gnawing ache (burning stomach pain), which occurs several days a week, it may occur 2 to 3 hours after a meal and mostly occurs in the night when the stomach is empty. Other symptoms include weight loss, heart burn, poor appetite, burping, bloating (a feeling of fullness in stomach), nausea (stomach upset), vomiting.

Emergency symptoms of an ulcer, which requires immediate medical attention are occurrence of sharp, sudden, persistent stomach pain, bloody or black stools, and bloody vomit. These symptoms may be due to ulcer burrowing inside the stomach or duodenal wall bleeding occurring due the acid or ulcer breaking into a blood vessel and obstruction of the path of food by the ulcer.