A mold-in fastening member which is composed of a strip of substrate, engaging elements formed on one surface of the substrate, and an elastomer layer completely surrounding the engaging elements, the substrate having slits or notches which extend from a widthwise central portion of the substrate to a widthwise end portion of the substrate. The mold-in fastening member bends in conformity with a two- or three-dimensionally complicated shape of a molded article. The mold-in fastening member prevents the surface having the engaging elements from being covered with a foamable liquid molding resin during a mold-in process, thereby preventing the engaging elements from losing the engaging function.