Background: Studies on the association between H. pylori infection and ABO/Rhesus blood groups have obtained controversial results. Objectives: To determine the association between H. pylori seropositivity among asymptomatic healthy persons and ABO/Rhesus blood groups, as well as certain demographic factors in Diyala province. Subjects and methods: This study was conducted in Diyala province for the period from November / 2010 to August 2011. 90 apparently healthy individuals were included. The age range was (14-43) years. 47 of them were males and 43 were females. ABO and Rh blood groups were determined by a standard hem agglutination test. Then sera were separated and submitted for the detection of anti-H.pylori IgG by enzyme linked immunosorbant assay (ELISA). Data were statistically analyzed. Results: the results showed that the anti-H.pylori IgG seroprevalence was (80%). The seroprevalence rate was significantly higher in female compared to male (86% vs 74.5%, p= 0.001). The highest infection rate was among the age group 24-33 years, with statistically insignificant difference (p= 0.10). The anti-H.pylori seropositivity rate among the A, B, AB, and O blood groups was 76.5%, 75%, 100% and 82.9% respectively (p= 0.5). the anti-H.pylori IgG positivity rate was higher in Rh negative as compared to Rh positive phenotypes (87.5% vs 79.3%,(p= 0.50). the anti-H.pylori IgG positivity rate was significantly higher (p= 0.05 ) among subjects with secondary school level as compared to other educational levels. Conclusion: It can be concluded that ABO and Rh blood groups may partly influence the rate of H.pylori infection, especially in female gender.