Objective To investigate the values of ASAS-endorsed disease activity score (ASDAS) and routine assessment of patient index data 3 (RAPID3) in assessing disease activity of patients with ankylosing spondylitis (AS) in China. Methods Questionnaires were used to obtain the general information and disease activity of 82 AS patients; and erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) were measured in the venous blood samples. Correlation analysis and kappa consistency test were used to compare the value of traditional measures for assessing disease activity of AS including Bath ankylosing spondylitis disease activity index (BASDAI) with the new measures including ASDAS and RAPID3. Results ASDAS-CRP and RAPID3 had a good consistency in assessing AS activity (kappa value: 0.788), but both of them had poor consistency with BASDAI (kappa values: 0.342, 0.367). BASDAI, ASDAS and RAPID3 were well correlated with doctor global assessment (DOCGL) and patient global assessment (PATGL), and ASDAS and RAPID3 had stronger correlation with DOCGL and PATGL than BASDAI did (the r values of ASDAS-CRP, ASDAS-ESR, RAPID3, and BASDAI with DOCGL were 0.684, 0.720, 0.642 and 0.576; and those with PATGL were 0.822, 0.816, 0.851 and 0.725, respectively). Conclusion ASDAS is superior to BASDAI in assessing the disease activity of AS, making it a new promising index for evaluating disease activity and worth promoting. RAPID3 is convenient, simple, and independent to laboratory findings, and it has a good reliability and validity in evaluating disease activity of AS.