消化性溃疡（英语：peptic ulcer disease、英语：peptic ulcer，简称PUD），又称胃及十二指肠溃疡。这是指胃、小肠前段（十二指肠）或幽门，有时也包含了食道下端的黏膜损伤（溃疡）。在胃发生的溃疡称作胃溃疡（英语：stomach ulcer），在小肠的开头部分所发生的溃疡则是十二指肠溃疡。最常见的症状是会因为吃东西而改善的上腹痛，或者晚上因肚子痛而醒来。胃溃疡的疼痛大多被用「烧灼感」或「闷痛」描述，其他常见的症状还包括打嗝、呕吐、不明原因的体重减轻、或是胃口不佳，但年纪较大的患者中约有三分之一完全没有症状 。胃溃疡若不处理，可能会演变成出血、消化道穿孔、或是胃出口阻塞，出血的发生率约为15%。

Peptic ulcer disease (PUD), also known as a peptic ulcer or stomach ulcer, is a break in the lining of the stomach, first part of the small intestine, or occasionally the lower esophagus. An ulcer in the stomach is known as a gastric ulcer while that in the first part of the intestines is known as a duodenal ulcer. The most common symptoms are waking at night with upper abdominal pain or upper abdominal pain that improves with eating. The pain is often described as a burning or dull ache. Other symptoms include belching, vomiting, weight loss, or poor appetite. About a third of older people have no symptoms. Complications may include bleeding, perforation, and blockage of the stomach. Bleeding occurs in as many as 15% of people.