Aim: We aimed to clarify the impacts of H. pylori infection on disease activity and clinical findings of AS. Material and Method: Forty-eight patients with AS were included in this study. The demographic data including age, sex, durations of the disease and medication of the patients were recorded. The laboratory analysis comprised Erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) and H. pylori antigen determination in gaita. The disease activity, functional disability and clinical status were assessed using the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), The Bath Ankylosing Spondylitis Functional index (BASFI) and The Bath Ankylosing Spondylitis Metrology Index (BASMI) respectively. We divided patients according to H. pylori antigen positivity in gaita as H. pylori positive and negative patients. Results: The mean age of patients was 41.9+11.8. CRP levels were slightly but not significantly higher in patients with positive H. pylori antigen compared to those in patients without H. pylori antigen in gaita (p=0.08). There was no significant difference in terms of ESR levels, BASDAI, BASFI and BASMI scores in patients with positive H. pylori antigen compared to those in patients with negative H. pylori antigen in gaita (p-values were >0.05 for all). In regression model BASDAI score was found to have no relationship with H. pylori antigen positivity, ESR and CRP levels (p-values were > 0.05 for all). Discussion: H. pylori seemed to have probable impacts on the disease activity of AS. Studies with greater patient population and longer follow-up periods are warranted to enlighten this issue.