Background: Because of the invasiveness of specimen collection for bacteriologic diagnosis and the expense of tests such as labeled urea breath tests, serology is the most feasible means of determining the population epidemiology of H. pylori. The aim of this study was to describe the SEROEPIDEMIOLOGY of H. pylori infection in Tabriz city.Methods: H. pylori -specific ELISA for the presence of IgG antibodies was performed on a representative sample of 21429 (70.02% F, 29.98% M) sera from Tabriz in two years (March 2012 to March 2014), using validated serosurveillance methods. Serum samples were analyzed through qualitative and quantitative methods for anti-H.pylori IgG antibodies with a research use only available enzyme immunoassay kit, that is, ''Anti -H.pylori IgG IBL ELISA". Anti- H.pylori IgG antibody levels greater than 12 U/ml was considered positive. Analysis was conducted using SPSS v15.0 and Epi info v3.2.2. The subjects were divided into nine groups according to age, Group I: Children under 10 years old, 1118 subjects, Group II: between 11-20 years old, 1756 subjects (1165 F, 591 M), Group III of between 21-30 years old, 4200 subjects (2976 F, 1224 M), Groups IV: 31-40 years old, 5072 subjects (3576 F, 1505 M), Group V: between 41-50 years old, 4299 subjects (3130 F, 1169 M), Group VI: between 51-60 years old, 3115 subjects (2307 F, 808 M), Groups VII: between 61- 70 years old, 1252 subjects (861 F, 409 M), Group VIII: between 71-80 years old, 483 subjects (284 F, 199 M), Group IX: between 81-90 years old, 116 subjects (64 F, 52 M).Results: The overall seroprevalence of H. pylori infection in Tabriz was 63.93% (63.77% F, 64.24% M), with no statistical difference between genders. Seropositivity rates increased progressively with age. In the first group, 23.61% the second group, 47.15%, the third group, 65.90%, the fourth group, 72.98%, the fifth group 62.59%, The sixth group, 69.92%, Group seven, 71.25%, Group eight, 60.45%, nine group, 62.93 %, The Anti H. pylori test was positive.Conclusion: The prevalence of infection with H. pylori in Tabriz City was lower than rates reported in other developed countries, at 63.93%. This study provides important baseline measurements for future preventive measures including vaccine research and development.