A substrate and an electronic device including the substrate are described. The substrate includes a first surface configured such that a semiconductor package or a semiconductor die is installable thereon, and a second surface facing the first surface, wherein, with respect to a central plane disposed between the first surface and the second surface at equal distances therefrom, a coefficient of thermal expansion in a first portion between the first surface and the central plane is configured to be higher than a coefficient of thermal expansion in a second portion between the second surface and the central plane configured to be. By using the substrate, undesirable overall shape deformation during semiconductor installation may be reduced or relieved.