Objective: Atherosclerosis is a chronic, progressive, inflammatory disease. Recognition of subclinical atherosclerotic vascular changes before clinical manifestation in an asymptomatic population is important for risk stratification and optimal management, which finally leads to the prevention of cardiovascular disease. We aimed to determine the risk of premature subclinical atherosclerosis by evaluating epicardial adipose tissue thickness (EATT) and arterial stiffness parameters in patients with ankylosing spondylitis (AS). Methods: We performed a prospective study of 60 consecutive patients meeting modified New York criteria for AS compared to 60 controls matched for age and sex. Patients with traditional cardiovascular risk factors were excluded. Arterial stiffness parameters and EATT (examined via echocardiography) values of all patients and control groups were measured. Results: There was no difference between basal characteristic and echocardiographic parameters in patients with AS and in the control group. EATT and pulse wave velocity (PWV) were higher in the AS patients compared to the control group. EATT was 5.74 ± 1.22 mm and 4.91 ± 1.21 mm (p < .001) and PWV was 9.90 ± 0.98 m/s and 6.46 ± 0.83 m/s (p = .009) in the AS and control groups, respectively. Also, PWV was significantly correlated with EATT, age, and central blood pressure in patients with AS. Conclusions: EATT and PWV, markers of atherosclerosis and cardiovascular disease, were significantly higher in patients with AS than the control group. In addition, in this study, it has been shown that there is a significant relationship between PWV and EATT in patients with AS.