A battery unit is provided under a floor panel. The battery unit is arranged between a pair of right and left side members. The battery unit is provided with a battery case. The battery case includes a tray member and cover member. Electric components are contained in the battery case. Beam members made of metal are attached to the tray member. Both end portions of these beam members are supported by the side members. The tray member includes a resin and insert members made of metal provided inside the resin. The insert members include metal plates arranged on the front side and rear side of the electric components.
