【Abstract】:Ankylosing Spondylitis (AS) is a common aotoimmune joint disease, it mostly occurs in young men and affects the quality of life of the patients seriously. Early diagnose of AS is more difficulty and the treatment is not satisfactory at present. Studies have been released that it has had a strong relationship with HLA-B27(Human leucocyte antigen-B27).The test of HLA-B27 was positive about 90% of AS patients and this outcome is very important for early diagnosis of AS. However the trial of HLA-B27 was negative still in the other 10% cases. This paper will review the diagnosis and treatments of AS and discuss the relationship between AS and HLA-B27.