Background and aims: Ankylosing spondylitis (AS) is an idiopathic chronic inflammatory disease mainly involves sacroiliac and axial joints; but it may also have extra-articular involvement. Accordingly, this study was designed to determine the frequency of cardiac involvement among patients with ankylosing spondylitis. Methods: This study was performed as a descriptive-analytical cross-sectional survey. In this study 50 consecutive patients with AS and 40 normal healthy subjects were enrolled and compared for cardiologic manifestations. Results: The frequency of cardiac involvement was similar between AS patients and normal subjects (P>0.05). However, there was significant difference between 2 groups in point of mitral valve prolapse and mitral regurgitation (P<0.05). Conclusions: Totally, according to the obtained results, it may be concluded that the frequency of cardiac involvement in AS patients and normal subjects were relatively similar