An unloading apparatus for unloading cargo items from a cargo group on a cargo bed includes a cargo bed lifting and lowering mechanism, a first detection unit that measures heights of cargos items and detects positions of cargo items forming the upper surface of the cargo group, a moving device that moves the cargo items to an unloading position, a second detection unit that detects whether a lower end of a cargo item being held by the moving device is above a position that is higher than the highest position of the cargo items at the upper surface of the cargo group, and a controller. The controller controls the raising and lowering of cargo bed in conjunction with the lifting of cargo items. The controller also controls the moving of the cargo items to the unloading position.