〔Abstract〕 Abstract Objective To analyze the correlation between different laboratory biomarkers and disease activity in an- kylosing spondylitis and to compare their specificity and sensitivity in assessing disease activity . Methods Spearman correlation or Pearson correlation was used to analyze the correlation between disease activity and labora- tory biomarkers . Receiver operating characteristic ( ROC) was used to compare the sensitivity and specificity of each laboratory biomarker in evaluating disease activity . Results Hypersensitive C-reactive protein , fibrinogen , D-dimer , erythrocyte sediment rate , C-reactive protein , immuno-inflammatory index ( platelet count ×neutrophil count/lymphocyte count ) , fibrinogen/albumin ratio , albumin and pro-albumin were correlated with disease activi- ty . The ratio of fibrinogen to albumin , fibrinogen , erythrocyte sedimentation rate , immuno-inflammatory index , C - reactive protein and hypersensitive C-reactive protein had good values in determining the disease activity . Conclu- sion Different laboratory biomarkers are correlated with the disease activity of ankylosing spondylitis , and some of them have better discriminating values for the disease activity .