In this paper, unmanned driving of robotic vehicle using magnetic marker is proposed. One of the most important component of autonomous vehicle is to detect the position of a magnetic marker on the road. In order to calculate the precise position of a magnet embedded on the road, the relation of magnetic field and a sensor is analyzed, and a new position sensing system using arrayed magnetic sensor is proposed. Also, the steering control system using a stepping motor is developed for driving by automatic mode as well as manual mode. For the verification of usability, the developed robotic vehicle is tested on magnetic road.