Objective: Behcet's disease (BD) is a chronic multi-system disease presenting with recurrent oral and genital ulceration, and relapsing uveitis. Left ventricular diastolic dysfunction, ventricular arrhythmia and sudden cardiac death have been documented in BD. P wave dispersion (PD) has been reported to be associated with inhomogeneous and discontinuous propagation of sinus impulses. PD has been reported to be longer in patients with BD. Nebivolol, besides its selective beta 1-blocking activity, causes an endothelium dependent vasodilatation through nitric oxide release. In this study, we searched for the effects of nebivolol on P wave duration and dispersion in patients with BD.