A storage device 1 includes: a case member 2; a lid member 3 configured to change between a closed position, an opened position, and a half-opened position; a fin member 4 configured to be pivotally supported on the second end portion 32 of the lid member 3; a cover member 5 configured to be positioned so as to be fixed relative to the case member 2, and to be disposed backward of the lid member 3 on the back side; and an urging member 80. When the lid member 3 changes between the half-opened position and the opened position, the projecting tooth portions 46 of the fin member 4 are in sliding contact with the recessed groove portions 55 of the cover member 5 by urging force of the urging member 80.