The invention of a large capacity and solve the inconvenience of the switch operation while minimizing the battery consumption by automatically turned OFF when the took off the shoes by the planar heating element is always in close contact with the sole of the foot and that it is possible to always hold the insulating state, while solving the problem of charging failure as using a battery according to a heat generating sock to hold the heating time;
The insole body, which side closed with a thick around the side of a thin form and a top surface and a bottom shell and then a cushion material, and a planar heating element to be incorporated for heating the front side of the insole body, is accommodated in the battery recess formed in the insole body rear side and a battery comprising the planar heating element and an electrical connection to the wiring, the switches of the substrate to be built so as to operate the planar heating element above the battery, is provided to be downwardly protruded in a side of the substrate positioned on the rear side one side of the sock body charge for charging is applied to an external power source to the terminal and the switch terminal is combined with the operating cold the planar heating element by a sliding operation, and a slide switch for selecting the high temperature operation and non-operation, the battery built into the front of the slide switch, it is characterized by constituting a connector.