PURPOSE:To carry out speedy operation as well as to reduce danger and difficulty in carrying a digging part of an unloader in and out of a hold. CONSTITUTION:On a continuous unloader constituted by supporting a hoisting boom by a revolving frame on a travel gantry and axially supporting a digging part on the head end of this hoisting boom, a travel device 12 of a travel gantry, a boom hoisting device 14, a boom revolving device 16, a digging part revolving device 18, a travel distance detector 13 to detect a travel distance of the travel gantry, a boom hoisting angle detector 15 and a boom revolving angle detector 17 are furnished. At the time of putting the digging part into and out of a hold, a control device 10 arithmetically processes it in accordance with detection signals from each of the detectors 13, 15, 17 and moves the digging part in the vertical direction by automatically controlling revolution by the boom revolving device 16 and travelling of the unloader by the travel device 12 interlocked with each other at the speed synchronized with horizontal movement of the digging part in the direction to offset the horizontal movement of the digging part caused by hoisting motion of the hoisting boom.