Aim The presence of anti-Saccharomyces cerevisiae antibodies (ASCA) is controversial in ankylosing spondylitis (AS). In this study, we aimed to investigate the prevalence of ASCA in AS and its relationship with disease activity and radiological damage in patients attending Sharkia governorate hospitals. Patients and methods Thirty AS patients and 30 apparently healthy volunteers were included in the present study. All patients were questioned for Bath Ankylosing Spondylitis Disease Activity Index, Bath Ankylosing Spondylitis metrology Index and Bath Ankylosing Functional Index (BASFI). Total Bath Ankylosing Spondylitis Radiology Index (BASRI-T) and ASCA levels were measured. Results ASCA IgA level was significantly higher in AS patients than in healthy controls (P < 0.001). The ASCA-positive group, although not significant, tended to have higher BASFI scores. ASCA IgA-positive patients had higher BASRI-T levels (P = 0.037). In AS patients, significant positive correlation was found between ASCA IgA level and BASRI-T and BASFI (r = 0.19 and 0.31, respectively, P < 0.05). Bath Ankylosing Spondylitis Disease Activity Index scores, BASFI and ASCA IgA positivity were significantly associated with increased BASRI-T (P= 0.01, 0.03 and 0.04, respectively). The most significant risk factor for increased BASRI-T is ASCA IgA positivity (P < 0.001). Conclusion ASCA IgA was detected more frequently in AS patients than in healthy controls. ASCA IgA could be considered a marker of severe radiological damage. Further studies are recommended to investigate ASCA level versus radiological damage and intestinal involvement in AS patients.