Resource consumption of a work vehicle in a specified work site is estimated more appropriately and a resource replenishment timing is calculated appropriately. A resource replenishing system for a work vehicle that effects work-implementing travel in a work site while consuming an amount of resource supplied from an energy source pack mounted on its vehicle body includes a consumption amount recording section 62 for recording an actual unit consumption amount of the resource together with work contents as work history, a work plan management section 52 for managing work plan information containing the work contents, an estimated consumption amount calculation section 101 for calculating an estimated unit consumption amount of the resource consumed per unit work amount of the work vehicle implemented based on the work plan information, with reference to the work history, and a replenishment management section 60 for calculating a replenishment timing for replenishing the resource to the energy source pack, based on the estimated unit consumption amount.