Background: Ankylosing spondylitis (AS) is a chronic inflammatory disorder that is characterized by inflammatory backache, enthesitis, sacroiliitis, peripheral arthritis, and anterior uveitis. Currently, a significant number of studies have been performed to seek markers to monitor disease activity in AS, and no novel markers satisfy the characteristics of use in the clinical setting. Objective: To assess serum Dickkopf -1 (DKK-1) level among AS patients and control individuals and evaluate their possible correlation with disease activity. Patients and Methods: This was a case-control study which comprised 40 AS cases and 40 gender matched healthy controls.ELISA was used in measuring DKK-1 concentration in the serum of studied subjects. Results: Mean ASDAS was 2.4±0.7, ranged from 0.8-4.1, mean BASFI was 3±1.9, ranged from 0.8-6.8, mean BASDI was 3.6±1.3, ranged from 0.9-6.8. AS patients demonstrated significantly greater DKK-1 level in comparison with controls (mean =197.7 vs. 87.1, p < 0.001). There were positive significant association between DKK-1 and AS disease activity measures. There were significant positive correlations between ESR, CRP, MS, ASDAS CRP, BASFI, BASDI and DKK-1 values. Conclusion: serum DKK-1 concentration is elevated in cases with AS, and it is significantly accompanied by disease activity and functional impairment.