Duodenal ulcer is a common and frequent disease, but the treatment of duodenal ulcer is now very well established and standardized. More than 90% of patients with duodenal ulcers are found to be infected with Helicobacter pylori, a bacterium that settles in the stomach but can cause duodenal ulcers through a series of complex mechanisms. Therefore, the current consensus among medical experts is that H. pylori testing is mandatory for patients with duodenal ulcers, whether active or scarred, and that if positive, standardized and relevant antimicrobial therapy is administered. If H. pylori is successfully eradicated, the ulcer can be cured and recurrence of the majority of ulcers is eliminated. Another reason for the development of duodenal ulcers is the use of aspirin and NSAIDs. Such patients need to stop taking them as much as other conditions allow and take drugs that inhibit gastric acid secretion, such as omeprazole-type drugs, which can basically heal in 4 to 8 weeks of treatment. However, such patients also need to be checked for H. pylori infection. Of course, there are other rare causes of duodenal ulcers, such as endocrine tumors, which are more specific. Targeted treatment is required. Therefore, when duodenal and ulcers are found, H. pylori should first be examined and treatment should be based on anti-H. pylori and suppression of gastric acid.