To realize a microwave heating-adjusting sheet useful as an auxiliary tool for intentionally adjusting excessive heating or irregular heating on a microwave heating treatment, and to provide a method for thermally cooking a food with the sheet, enabling to, if necessary, accelerate the heating of the food or stop the heating of the food by the use of the sheet.

This microwave heating-adjusting sheet is produced by disposing a heat-generating part 2 capable of being heated to a high temperature or a desired temperature by the irradiation of the microwaves on the whole or partial part of a sheet-like material 1. The method for cooking a food with the microwae heating-adjusting sheet comprises wrapping, laying, covering, etc., a food (including a packed food) with the microwave heating-adjusting sheet, placing the food in a microwave oven, and irradiating the food with microwaves to cook the food by the heat generation with the microwave and simultaneously auxiliarily cook the food by the heat generation of the microwave heating-adjusting sheet.