A reflective substrate is provided, in which an electrode made of a material having an optical reflecting function is provided above an insulating base substrate and an upper surface of the electrode has a continuous wave shape without any flat portions. A method for manufacturing the reflective substrate includes the steps of: forming a plurality of convex portions with two or more different heights in a region where the electrode is provided; forming a polymer resin film, which has an upper surface in a continuous wave shape without any flat portions, on the substrate with the convex portions; and forming the electrode made of a material having an optical reflecting function on the polymer resin film so that the electrode has a continuous wave shape. A liquid crystal display device using the reflective substrate is provided, which includes: a reflective substrate in which an electrode made of a material having an optical reflecting function is provided on an insulating base substrate, and an upper surface of the electrode has a continuous wave shape; a second substrate provided opposing the reflective substrate; and a liquid crystal layer sealed between the reflective substrate and the second substrate.