To evaluate the effect of kinesiophobia on quality of life in patients with ankylosing spondylitis (AS). Material and Methods: This study included 38 patients with AS and 38 controls. Patients were assessed according to the grades of radiographic sacroiliitis and kinesiophobia scores (high (≥37) and low (<37)). Short form-36 (SF-36) was used to evaluate the quality of life and the Tampa kinesiophobia scale (TKS) was used to evaluate the presence of kinesiophobia. The correlations were analyzed. The 'Bath Ankylosing Spondylitis Disease Activity Index' (BASDAI) was used to assess the disease activity and, the visual analogue scale (VAS) was used to evaluate the pain objectively. Results: In patient group, kinesiophobia score was significantly higher (40.92±6.65) than in healthy controls (36.66±8.05) (p<0,05). All SF-36 sub-parameters, especially general health and physical function, were significantly lower in patients compared to healthy controls (p<0,05). Patients with high kinesiophobia score had a higher pain score and lower general health score compared to the patients with low kinesiophobia score (for pain score 4.83±3.09, 2.89±1.27, respectively, and for general health score (35.26±20.90, 57.22±20.02, respectively) (p<0.05). Emotional role limitation score was lower in patients with radiographic sacroiliitis (33.30 (0-67.10)) compared to the patients with non-radiographic sacroiliitis (83.50 (66.70-100)). Other SF-36 sub-parameters, BASDAI and VAS scores did not exhibit a significant difference between the groups (p>0.05). Conclusion: Kinesiophobia is more common in patients with ankylosing spondylitis compared to healthy controls, and quality of life is impaired. The presence of kinesiophobia is associated with quality of life variables, such as increased pain and impaired general health. Therefore, each patient should be evaluated for kinesiophobia and quaility of life at the beginning of treatment.