This paper describes the development of finger rehabilitation device for post stroke patient. The device applied a wire-driven mechanism concept for hand grasping and releasing based on finger extension and flexion movement. The prototype of wire-driven mechanism is developed based on human hand anatomy and movement study. Three different designs and prototype testing are conducted to testify the wire-driven mechanism concept as the finger rehabilitation device. The device can assist repetitive finger extension and flexion movement during the rehabilitation period. The actuating system of the device enables the patient to control the movement by using the self-motion control concept. Pilot test for the device will be conducted after the final prototype is developed.