A powder disperser comprises a nozzle having a narrow discharge port for discharging a powder. A high speed air flow discharge port forms a narrow air port encompassing the outer circumference of the discharge port of the nozzle and is inwardly slanting at an acute angle relative to the discharge direction of a powder flow from the nozzle. A powder dispersing passage is narrowly formed on the downstream side of the nozzle in a circular tube like shape or in a radial shape along the outer wall surface continuing from the outer wall of the high speed air flow discharge port. The powder discharge passage is connected to the powder supply port of a classifier located downstream next to the disperser.