Abstract: Objective To study the diagnostic characteristics of ankylosing spondylitis in female patients. Methods Clinical characteristics of 93 female and 191 male patients with ankylosing spondylitis,admitted to our department form January 1999 to January 2009,were retrospectively analyzed. Results The average age of the 93 female ankylosing spondylitis patients was 35.05 years and the course of disease was 7.48 years.Of the 93 patients,68（73.12%） had a delivery history and 59（63.40%） were positive for HLA-B27.The chief complaint was pain in hip,pubis and heel.CT or X-ray showed grade 1 unilateral and bilateral ankylosing spondylitis in 39 and 25 patients respectively,grade 2 unilateral and bilateral ankylosing spondylitis in 15 and 8 patients respectively,grade 3 bilateral ankylosing spondylitis in 7 patients,and no grade 4 ankylosing spondylitis in any patients. Conclusion The clinical characteristics of female ankylosing spondylitis patients include a long disease course and mild symptoms mainly manifested as peripheral joint pain with no typical imaging findings and a low disability.The symptoms may exacerbate after delivery.