The aim of the present study was to investigate whether virulent CagA positive Helicobacter pylori strains are those preferentially related to abdominal aortic aneurysm (AAA) rupture. Several microorganisms have been linked to aneurysm development. Chronic Chlamydophila pneumoniae infection has been suggested as a possible contributing factor for the development and expansion of AAA. Previous studies have shown increased risk of carotid atherosclerosis and coronary heart disease in subjects harbouring CagA positive strains of H. pylori. The relevance of CagA positive H. pylori involved in the processes underlying aneurysmal development, expansion, and rupture is unknown. In a case-control study, 119 patients with AAA and 36 matched controls were prospectively investigated with H. pylori serology. Patients with ruptured AAA have similar levels of IgG antibodies against H. pylori to patients with electively operated AAA, small AAA, and controls. In conclusion, this study fails to demonstrate a connection between H. pylori CagA seropositivity and abdominal aortic aneurysm rupture.