In this paper, the gait parameter detection system using an infrared rays elements was developed. This system consist of the transmission unit and receiver of an infrared LED light and the gait parameter were calculated by the non-transmission timing of infrared LED light from user’s leg movement Based on this method, we calculated the velocity of gait and gait stride of the person during the gait motion on the treadmill. To confirm the effectiveness of this system, we analyzed the real velocity of the treadmill using tachometer on treadmill compared with controlled velocity of treadmill.