Context The association between obesity and Helicobacter pylori (H. pylori) infection remains controversial. Aims The objective is to investigate the relationship between obesity and H. pylori infection, as diagnosed on the basis of a 14C urea breath test (14C-UBT) and waist circumference (WC). Settings and design A retrospective cross-sectional study was performed at Health management center of a Tertiary care teaching hospital in Southwest of China. Materials and methods Clinical information of 76,915 individuals (46,003 men and 30,912 women) with 44.0 (35.0-51.0) years was extracted from medical record. H. pylori infection was diagnosed by a positive 14C-UBT, and obesity was defined as WC ≥ 90 cm in men and ≥ 80 cm in women. Statistical analysis Descriptive statistics, Student's t test, Mann-Whitney U test, and chi-square test, followed by binary logistic regression were performed in SPSS. Results The overall prevalence of H. pylori infection was 39.95%. The prevalence of H. pylori infection in subjects with central obesity was significantly higher than that in normal-WC subjects (42.20% vs. 39.10%, p < 0.001). WC was significantly higher in H. pylori-positive subjects compared with H. pylori-negative subjects (p < 0.01). There was a linear association between WC quintiles and H. pylori infection prevalence. After adjusting for confounders, central obesity was associated with H. pylori infection (OR = 1.052, 95% CI, 1.009-1.096, p = 0.02). Conclusions Central obesity is associated with H. pylori infection after adjusting for multiple confounding factors such as age, gender, and lifestyle characteristics.