Objective:To investigate the Helicobacter pylori ( H. pylori) infection of Tibetan families and individuals in the Western Sichuan Plateau region and explore the related factors which affected H. pylori infection. Methods:This was a single-center cross-sectional study. Questionnaires were collected from 50 Tibetan families including 155 individuals in Western Sichuan Plateau region during March to May 2023. The 13C-urea breath test was performed to confirm the current infection status of participants. Binary logistic regression were used to analyze the related factors associated with H. pylori infection. Results:Among the 50 Tibetan households, the individual-based H. pylori infection rate was 47.10%(73/155), with two out of nine children and 48.63%(71/146) adults infected. The age group of 18 to 40 years had the highest infection rate (55.00%, 11/20). The prevalence of infection based on family was 80.00%(40/50), of which 16.00%(8/50) had all family members infected. Of the 59 couples surveyed, 23.73%(14/59) were both infected, and 45.76%(27/59) had one person infected. Of the six families which had children and adolescents, two households had their children infected. Logistic regression analysis showed that size of the family was a factor related to H. pylori infection (odds ratio=3.038, 95% confidence interval 1.043 to 10.491, P=0.042). Conclusions:The family-based H. pylori infection rate is relatively high in Tibetan residents in the Western Sichuan Plateau, and larger family size is related with higher risk of H. pylori infection within the family.