BACKGROUND Rheumatic mitral stenosis (MS) is still a common disease in developing countries with high morbidity and mortality rates. The purpose of the study was to evaluate arterial stiffness in severe MS before and after percutaneous mitral balloon valvuloplasty (PMBV). METHODS Thirty patients with MS in sinus rhythm requiring PMBV and 20 age-gender matched healthy volunteers. The analyze of pulse wave velocities (PWV) were performed using of the carotid artery at the femoral by PWV technique on patients at baseline and a week after PMBV. RESULTS The values of PWV were significantly decreased after successful PMBW in MS patients. Mitral mean gradients and systolic pulmonary artery pressures (sPAP) both on echocardiography and catheterization also had a significant decrease after PMBW. The mitral valve areas were significantly increased after PMBW. There was a highly significant negative correlation between mitral valve areas and PWV values. A highly significant positive correlation was seen between mitral mean gradient on catheterization and PWV (r = 0.830, p 〈 0.001). There was also a significant correlation between sPAP on catheterization and PWV values (r = 0.639, p 〈 0.001). Echocardiographic mitral mean gradients and PWV were highly positive correlated with each other (r = 0.841, p 〈 0.001). The sPAP on echocardiography had also a highly positive correlation with PWV (r = 0.681, p 〈 0.001). CONCLUSIONS Mitral stenosis is a cause of impaired arterial stiffness and after the enlargened mitral valve area arterial stiffness improved in patients with MS.