Helicobacter pylori (H. pylori) is one of the causes of gastritis, peptic ulcer disease, gastric cancer and MALT-lymphoma. The frequency of H. pylori infection is different in various regions of the world and dependent on age, socioeconomic and hygiene status. The objective of this study was to assess seroprevalence and the associated socioeconomic and sociodemographic characteristics influencing H. pylori infection in children and adults in Polish population.