A package of the present invention has a laminate structure of a plurality of ceramic layers, and includes a cavity for housing a light emitting element. A mount surface is defined on a side surface parallel with the depth direction of the cavity. A pair of external electrodes each including a charged electrode portion and a coated electrode portion are formed over the entire length in the laminating direction at two corners defined by intersection of the mount surface and two side surfaces perpendicular to the mount surface. When the package is mounted, a pair of charged electrode portions and a pair of coated electrode portions are soldered to a surface of a substrate.