A method for manufacturing a semiconductor device with a treated member, includes: subjecting an adhesive support having a substrate and an adhesive layer capable of increasing or decreasing in adhesiveness upon irradiation with an actinic ray, radiation or heat to irradiation of the adhesive layer with an actinic ray, radiation or heat, adhering a first surface of a to-be-treated member to the adhesive layer of the adhesive support, applying a mechanical or chemical treatment to a second surface different from the first surface of the to-be-treated member to obtain a treated member, and detaching a first surface of the treated member from the adhesive layer of the adhesive support, wherein the irradiation of the adhesive layer with an actinic ray, radiation or heat is conducted so that adhesiveness decreases toward an outer surface from an inner surface on the substrate side of the adhesive layer.