We examined the age of acquisition of Helicobacter pylori infection in a prospective study that was conducted among 231 Israeli Arab children. Helicobacter pylori was identified in stool specimens collected at ages 2, 4, 6, 8, 12 and 18 months, using a monoclonal stool antigen immunoassay. Information on household characteristics, breastfeeding, antibiotic use and hygiene practices was obtained. The incidence of H. pylori infection was 33.3%. The estimated mean age of H. pylori infection acquisition was 14 months. The determinants of H. pylori infection were living in a low socioeconomic status (SES) village: OR 9.60 (95% CI 2.91-31.68, p < 0.001); low paternal education: OR 3.35 (95% CI 1.21-9.29, p = 0.02); and boiling feeding bottles and nipples at low frequency: OR 7.12 (95% CI 1.82-27.86, p = 0.005). In conclusion, H. pylori infection is acquired at a higher rate in low SES settings. Parental education and hygiene play an important role in H. pylori acquisition in infancy.