OBJECTIVE To study the prevalence and determinants of Helicobacter pylori (H. pylori) infection among coal miners and to seek for competent preventive measures. METHODS 425 coal miners from three coal mines, Tangshan, Daxing, and baodian were chosen under stratified random cluster sampling. Face to face interview was conducted to fill the unified questionnaires by trained interviewers. 306 subjects underwent gastroenduoscopy to detect the situation of the gastroenduodenal diseases, according to the Sydney System of diagnosis. Mucosa biopsies were also undertaken according to the regulated location for culture of H. pylori and for pathological examination. Blood samples were obtained to detect the anti-HpU-IgG by enzyme-linked immunosorbent assay (ELISA). H. pylori infection was determined through culture and ELISA but confirmed under the standards set at the National Congress on Gastroduodenal Diseases in 1999. RESULTS Among 425 eligible coal miners being tested, 297 (69.9%) were H. pylori positive and the rate for those working underground (74.0%) was higher than that of those working on ground (P=0.004). No difference was found among coal miners between the three mines (P >0.05). Age, living conditions in childhood, number of current family members, the amount of alcohol intake and ways of eating at home were strongly associated with the status of H. pylori infection. CONCLUSIONS Difference of H. pylori infection prevalences between the underground and the aboveground coal miners was noticed. Determinants that influencing the H. pylori infection would include socioeconomic factors, individual habits and ways of eating at home.