PURPOSE: To enable different goods to be selectively loaded on a dump truck so as to improve the efficiency of transportation by pivotably mounting a pair of deck boards inside a deck case and providing sheets as to be spread out and folded in the front and rear positions between those deck boards.

CONSTITUTION: When cement, for example, is transported in a go drive, each of the left and right deck boards 14 is turned upwards about a shaft 12 by the action of a hydraulic cylinder which is disposed on the front wall of a deck case, whereby spreading out front and rear sheets 17 and 18, while forming an accommodation room by means of a pair of the deck boards 14, a floor board 4 and the front and the rear sheet 17 and 18. The cement is supplied in the accommodation room and transported to a predetermined location. For the transportation, a hood opening and closing means 22 is driven to have a sheet 25 cover the upper part of the deck case 3. The cement is evacuated in the due location and thereafter if coal, for example, is transported in the back drive, the deck boards 14 are turned downwards to have the sheets 17 and 18 folded under the deck boards 14 and the coal is then loaded inside the deck case 3.