PURPOSE: An optical storage is provided to realize small-sized, light-weight and highly reliable optical storage device. CONSTITUTION: The optical storage device is provided with a cartridge holder to which a cartridge housing an optical storage medium is inserted, a turntable unit composed of a turntable for rotationally driving the optical storage medium and a metal plate with a slide part for holding the turntable, a loading/unloading mechanism having a loading plate where a guide with a slope is formed for sliding the slide part on the slope of the guide and elevating/lowering the turntable by sliding the loading plate, and a drive base where the cartridge holder is loaded on the lower surface side and the turntable unit and the loading/ unloading mechanism are loaded so as to engage the slide part with the guide on the upper surface side of the cartridge holder.
