Atherosclerosis has two key components, thickening and stiffening of arterial wall. These parameters are quantified ultrasonographically by IMT (intima-media thickness) and PWV (pulse wave velocity). In the present study, we determined the FA IMT (IMT of the bilateral femoral artery) and PWV of femoral-ankle (PWV fa) and brachial-ankle (PWV ba) segments in order to examine whether the degree of atherosclerosis is different between paretic and non-paretic lower limbs in 24 patients with hemiparesis. The values of PWV fa, PWV ba and FA IMT were all significantly greater on the paretic than the non-paretic side. Furthermore, significant decreases in masses of muscle, bone and fat, determined by dual-energy X-ray absorptiometry, were observed in paretic lower limbs compared with the non-paretic side. PWV fa correlated significantly and negatively with muscle mass ( r =-0.488, P =0.0004) and tended to correlate negatively with BMC (bone mineral content; r =-0.264, P =0.069) when statistical analyses were performed with the paretic and non-paretic sides together. Multiple regression analysis elucidated that the muscle mass was associated significantly with PWV fa and PWV ba, independent of age, duration after cerebrovascular accident, gender, bone and fat mass and FA IMT. The muscle mass was still associated with increased PWV fa and PWV ba when multivariate analysis was conducted independently in the paretic and non-paretic sides. In summary, our results indicated that arterial thickening and stiffening were greater on the paretic than the non-paretic side and suggested that a decrease of muscle mass might be associated with increased arterial stiffening in the paretic lower limb.