PROBLEM TO BE SOLVED: To provide a heat treatment apparatus for efficiently heat-treating an object such as a pack food material in a small space.SOLUTION: This heat treatment apparatus 1 includes a holding part 25 holding an object to be heat-treated, a nozzle 30 jetting a heat medium M to the object to be heat-treated, a heat medium storing part 25A formed on the lower part of the holding part 25 and receiving the heat medium M jetted from the nozzle 30, a heat medium circulating circuit 40 circulating the heat medium M in the heat medium storing part 25A to the nozzle 30, and a temperature adjusting means. The temperature adjusting means has a heating part 51 heating the heat medium and a cooling part 60 removing heat from the heat medium. Temperature adjustment of the heat medium M is performed based on the temperature of the heat medium M.
