The invention discloses a preparation method for a high-temperature resistant copper foil adhesive. The preparation method comprises the following steps: preparing an epoxy acrylate adhesive by taking hydroxyl-containing epoxy resin and acrylic acid as main raw materials; preparing a bismaleimide adhesive by taking bismaleimide resin as a raw material; and mixing the adhesives prepared from the first and second steps according to a certain proportion, adding auxiliaries and then diluting, thereby acquiring a target product, namely the high-temperature resistant copper foil adhesive. The high-temperature resistant copper foil adhesive prepared by using the preparation method provided by the invention has the advantages of excellent viscosity controllability, wider adjustment scope, excellent manufacturability, thermolysis temperature Tonset more than 300 DEG C, excellent property for splicing a metal copper-copper substrate and a copper-phenolichydroxyl polyimide film, stretching shearstrength reaching up to 30MPa, and 90-degree peel strength reaching up to 2.0kg/cm (substrate: copper-phenolichydroxyl polyimide film).