Abstract: Objective: To investigate the relationship between HLA-B27 and ankylosing spondylitis in patients from the north of Anhui province.Methods: The method of enzyme-linked immunosorbent assay was used to determine the HLA-B27 in 27 patients with AS from north Anhui.Results: HLA-B27 (+)was more frequently detected in the male patients than in the female,while HLA-B27 (-)was more often seen in the female patients than in the male.The difference was distinct between the two groups (P=0.001).The B27 (+)group usually demonstrated central axis joints symptoms,while the B27 (-)group periphery joints symptoms.Before treatment,the level of erythrocyte sedimentation and C-reactive protein of B27 (+)group was higher than that of B27 (-)group (P<0.05 and P<0.01).And after 3 to 6 months' treatment,the level of erythrocyte sedimentation and C-reactive protein in B27 (+)group was higher than that in B27 (-)group (P<0.001).There was no significant difference in the age between the two groups (P>0.05).Conclusions: There is relationship between the gender and the severity of ankylosing pondylitis in the Han nationality of north Anhui.Ankylosing pondylitis with HLA-B27 (+)is more difficult to control.