A new FES-cycling device (Figure.1), modified from our previous prototype (Chen, 2004), was used in this study. This device combines FES with a cycling system equipped with ankle-foot orthoses. The FES stimulates the quadriceps and hamstring when the affected leg sweeps past a specific angle. The aims of this study were to determine whether a short-term of FES-cycling program in stroke patients can reduce the muscle tone of the affected leg immediately and influence the postural control of the subjects.