An apparatus for controlling operation of an autonomously navigating utility vehicle equipped with a prime mover to travel about a working area delineated by a boundary wire laid thereat in order to perform work autonomously, the apparatus comprising: a magnetic sensor that is configured to produce an output indicating a magnetic field strength generated by electric current passing through the boundary wire; a position detector configured to produce an output indicating a position of the vehicle; a map generating unit that is configured to operate in a trace mode executed before a work mode to circuit the vehicle along the boundary wire based on the output from the magnetic sensor, to detect the position of the vehicle based on the output from the position detector from start to finish of the trace mode, and to generate a map of the working area based on the output of the position detector when the vehicle is driven in the trace mode, characterized in that the map generating unit is further configured to transmit the map to an external device through a wireless module; a data acquiring unit that is configured to acquire from the external device through the wireless module, data indicating an imaginary boundary line (L1, L2, L3) designated by an operator of the external device that divides the working area into multiple regions (AR1, AR2, AR3, AR4) to be serviced by the vehicle and data indicating a preferential working region (ARa) among the multiple regions (AR1, AR2, AR3, AR4); and a travel controlling unit that is configured to operate in the work mode to discriminate whether the vehicle has reached the boundary wire based on the output of the magnetic sensor, and to control operation of the prime mover to make the vehicle turn toward the inside of the working area when it is discriminated that the vehicle has reached the boundary wire, wherein the travel controlling unit is configured to operate in the work mode to control operation of the prime mover to make the vehicle travel autonomously in the preferential working region (ARa) by discriminating whether the vehicle has reached the imaginary boundary line based on the output of the position detector, and controlling operation of the prime mover to make the vehicle turn toward the inside of the preferential working region (ARa) when it is discriminated that the vehicle has reached the imaginary boundary line. a magnetic sensor that is configured to produce an output indicating a magnetic field strength generated by electric current passing through the boundary wire; a position detector configured to produce an output indicating a position of the vehicle; a map generating unit that is configured to operate in a trace mode executed before a work mode to circuit the vehicle along the boundary wire based on the output from the magnetic sensor, to detect the position of the vehicle based on the output from the position detector from start to finish of the trace mode, and to generate a map of the working area based on the output of the position detector when the vehicle is driven in the trace mode, characterized in that the map generating unit is further configured to transmit the map to an external device through a wireless module; a data acquiring unit that is configured to acquire from the external device through the wireless module, data indicating an imaginary boundary line (L1, L2, L3) designated by an operator of the external device that divides the working area into multiple regions (AR1, AR2, AR3, AR4) to be serviced by the vehicle and data indicating a preferential working region (ARa) among the multiple regions (AR1, AR2, AR3, AR4); and a travel controlling unit that is configured to operate in the work mode to discriminate whether the vehicle has reached the boundary wire based on the output of the magnetic sensor, and to control operation of the prime mover to make the vehicle turn toward the inside of the working area when it is discriminated that the vehicle has reached the boundary wire, wherein the travel controlling unit is configured to operate in the work mode to control operation of the prime mover to make the vehicle travel autonomously in the preferential working region (ARa) by discriminating whether the vehicle has reached the imaginary boundary line based on the output of the position detector, and controlling operation of the prime mover to make the vehicle turn toward the inside of the preferential working region (ARa) when it is discriminated that the vehicle has reached the imaginary boundary line.