There is provided an adhesive sheet that has initial adhesiveness, can realize bonding between metals, between a metal and an organic material, and between organic materials, and can retain an excellent adhesion strength without undergoing a temperature change. The adhesive sheet comprises a first release paper, an adhesive layer, and a second release paper stacked in that order, the adhesive layer containing an adhesive, the adhesive containing at least an acrylic resin, an epoxy resin, and a curing agent, the content of the epoxy resin being 175 to 300 parts by weight per 100 parts by weight of the acrylic resin.