Provided is an insulating sheet capable of effectively enhancing thermal conduction and adhesiveness. The insulating sheet according to the present invention contains a thermosetting component and a thermally conductive filler, the thermally conductive filler contains boron nitride, the insulating sheet has a first surface on one side in a thickness direction and a second surface on the other side in the thickness direction, and a first content of the boron nitride in 100% by volume of a region having a thickness of 10% of a thickness of the sheet, from the first surface toward the second surface is smaller than a second content of the boron nitride in 100% by volume of a region having a thickness of 90% of a thickness of the sheet, from the second surface toward the first surface.