The present invention includes: a map information storage unit 18 storing map data 18A representing a travelable area for a dump truck 7; a work machine information accumulation unit 19 accumulating position data 6A and operational data 6B of a hydraulic excavator 6; an operational range arithmetic processing unit 21 calculating an operational range of the hydraulic excavator 7 on the basis of the position data 6A and the operational data 6B accumulated in the work machine information accumulation unit 19; and a map information update unit 22 verifying the operational range of the hydraulic excavator 6 calculated by the operational range arithmetic processing unit 21 against the map data 18A stored in the map information storage unit 18 in order to correct the boundary 18a of the loading site 1 in the map data 18A and then update the map data 18A.