PROBLEM TO BE SOLVED: To provide a heating device for food in a food container with which preliminarily packaged food can be heated with steam without requiring any large-scale device.SOLUTION: A heating device for food in a food container includes: a container 1 (food container) housing a plurality of food materials 2a, 2b； a cooking chamber 8 (cooking container) housing the container 1； and a steam generation device 14 supplying steam into the cooking chamber 8. The container 1 includes opening holes 4a, 4b, 4c which are made into the container 1 and through which the inside space and the outside space of the container 1 are communicated with each other, and a space between the inner wall of the container 1 and the food materials 2a, 2b and/or spaces 6a, 6b, 6c, 6d (spaces surrounding the food materials) formed between the food material 2a and the food material 2b, makes the spaces 6a, 6b, 6c, 6d communicate with the outside space via the opening holes 4a, 4b, 4c, and supplies the steam into the cooking chamber 8 to heat the food materials with the steam.【課題】大がかりな装置を必要としないで予め容器に入った状態の食材を蒸気加熱できる食材容器入り食材用加熱装置を提供すること。【解決手段】複数の食材２ａ、２ｂを収容する容器１（食材容器）と、容器１を収容する調理庫８（調理容器）と、調理庫８内に蒸気を供給する蒸気発生装置１４と、を備え、容器１は、容器１に設けられ容器１の内側空間と外側空間とを連通する開口穴４ａ、４ｂ、４ｃと、容器１の内壁と食材２ａ、２ｂとの空間及び／または食材２ａと食材２ｂとの間に設けた空間６ａ、６ｂ、６ｃ、６ｄ（食材周囲空間）と、を有し、空間６ａ、６ｂ、６ｃ、６ｄと外側空間とを開口穴４ａ、４ｂ、４ｃを介して連通し、調理庫８内に蒸気を供給し蒸気加熱する。【選択図】図１
