A heat insulation sheet includes a fiber sheet, a resin layer provided on a surface of an outer peripheral portion of the fiber sheet, and a silica xerogel disposed in spaces of the fiber sheet. The fiber sheet includes fibers forming spaces among the fibers. The resin layer is denser than the fiber sheet and made of thermoplastic resin. The silica xerogel is held in the plurality of fibers. This heat insulation sheet is excellent in adhesiveness, and is easily attached to a protective sheet or a frame to be fixed.