Unmanned off-highway dump trucks have been developed as the first step toward entire mine automation. The vehicles are operated on a teaching-playback basis. That is, an operator once drives a truck along a desired path, which is stored in IC memories as a series of points. Then microprocessors control the car so that it runs on the route repeatedly. The data can be saved in IC cards. System supervisors can select any one course in a card set on board. The card can be detached and kept for the future use. Also it can be copied to spread the course data to other vehicles when multiple trucks are operated in a fleet. When a vehicle is inside a loading area, an operator of a loading machine can drive the truck by radio control so that the operator can stop the truck at any point where he/she wants to load. The entire system comprises several chief subsystems, man machine interface including radio control, navigation, vehicle control, data link, and safety unit. These subsystems ensure easy, safe, precise and reliable automatic unmanned dump truck operations, which decrease running cost of mines, protect human operators from accidents, reduce labor problems, and liberate workers from tedious and exhausting jobs. In this paper, a general view of the system and details of vehicle control are described.