In an apparatus controlling an autonomously navigating utility vehicle with a prime mover to travel about a working area delineated by a wire, are provided a travel controlling unit (312) controlling operation of the prime mover to make the vehicle travel along the wire in trace mode based on a value detected by one magnetic sensor while positioning other magnetic sensor inside the wire, a route generating unit (313) generating a route along the boundary based on detected turning angle and travel distance in trace mode, a memory unit (314) memorizing the magnetic field strength detected by the other magnetic sensor in the trace mode in association with the travel route, and a position identifying unit (315) compareing the magnetic field strength detected by the magnetic sensors with one memorized in the memory unit and identifies the vehicle position in the work mode based on a result of the comparison.
