The role of H. pylori infection in the pathogenesis of duodenal ulcer is well known. However, the correlation between perforated ulcer and H. pylori infection shows a great debate in literature.The relation of H. pylori and duodenal ulceration was proved, and many mechanisms by which the pathogenesis of ulceration occurs were discovered. These mechanisms include many virulent factors whether morphological like the flagella, or through the secretion of toxins.