To provide a powder heat treatment device that smoothly extracts gas to be generated in a heating stage from a powder material heated at a high temperature around or higher than 1,500 °C, and prevents a bridge from being generated in a cooling stage, while ensuring flowability of the powder material or uniformly heating the powder material.

The powder heat treatment device includes: an upper charging part 3 for charging a powder material P; a guide shaft 7 for guiding the powder material gravitationally downward for heat treatment; a lower discharging part 4 for discharging the powder; an upper agitation member 20 inserted downward from above the guide shaft to agitate a powder surface part and periphery thereof in the guide shaft; a lower agitation member 5 inserted upward from below the guide shaft at a distance from the upper agitation member 20 to agitate the powder material in the guide shaft.