PROBLEM TO BE SOLVED: To provide a heating element in which a heating composition does not lean to one side in a packaging material by action of gravity, which can rapidly rise an increase in a temperature and can maintain at an optimal temperature.SOLUTION: The heating element includes the packaging material 30, and a laminate 1 for manufacturing a heating element housed in the packaging material 30. The laminate 1 for manufacturing the heating element includes the heating composition 2, first fiber layers 3a, 3b laminated thinly above and below the heating composition 2, second fiber layers 4a, 4b laminated thinly above and below the first fiber layers 3a, 3b. The heating composition 2 contains a thickener 21c mixed in an exothermic agent 21a, and an exothermic auxiliary 21b.
