To provide a device for efficiently and safely conveying vegetative earth and sand for greening a roof floor to the roof floor.

By the structure of the device, a suction pipe 15 on the upstream side of a diffuser pipe 9 has an outside air sucking hole 12 formed therein for communicating with outside air. An area in which the outside air sucking hole 12 intersects the upstream side of the suction pipe 15 and the diffuser side of the same is formed such that an outside air sucking hole edge, an upstream-side suction pipe edge, and a diffuser pipe-side suction pipe edge are located on the same circumference, and an impeller 11 for rotating at a constant speed is mounted at the center of the circumference. When the impeller 11 rotates with high-pressure air blown from a jet nozzle 14, a state that a suction hose 2 is released from the diffuser pipe 9, and a state that the suction hose 2 communicates with the diffuser pipe 9, alternately appear, and therefore earth sucked by the suction hose 2 and air are alternately conveyed up to the roof floor of a building.