It is very important to use an expansion interface for the handicapped person by injury of spinal cord. However, these persons cannot use mouse or keyboard, in order to operate PC. For this reason, they must purchase special devices to operate PC. Such equipments are too expensive, user-unfriendly and dissatisfaction for their requests. To improve these situation, we have developed PC-Interface named "Motion Link InterFACE" for handicapped person. This system traces the movement of the face, using a USB-camera and a retro-reflective marker. By the face motion, the handicapped person can use to emulate mouse operations or keyboard on PC. The cost of this system is lower than other same input devices.