Objective To retrospectively analyse the detection results of human leukocyte antigen(HLA) B27,and discuss its diagnosis value in disease such as ankylosing spondylitis(AS).Methods HLA-B27 detection was performed on 1 335 suspected AS patients treated in the hospital from January 2015 to June 2016 by using multiparameter flow cytometry instrument.The test results showed 201 patients were diagnosed with AS(AS group),1 134 patients were diagnosed with rheumatoid arthritis and other related diseases (non AS group).The test results were shown by using mean fluorescence intensity and positive lymphocyte expression rate.n addition,120 healthy people were enrolled as the control group in the physical examination center of the hospital.Results The positive rate of HLA-B27 screening in suspected AS patients was 15.73% (210/1 335),and the positive rate of HLA-B27 screening in the control group was 2.50% (3/120).The positive rate of HLA-B27 screening,the rate of cell expression and the average fluorescence intensity of AS group were 92.03%(185/201),(85.34±17.99)%,8.74±4.20,significantly higher than the non AS group and the control group(P<0.01).There was no significant difference between the control group and the non AS group (P>0.05).HLA-B27 screening positive patients were mainly concentrated in adolescence,and the positive rate of male was higher than that of female (P<0.05).Conclusion Flow cytometry examination of HLA-B27 can provide important basis for the diagnosis and differential diagnosis of AS.