A toner cartridge can be attached to and detached from an apparatus main body. The toner cartridge includes an outer housing having a substantially rectangular upper cross section and a substantially semi-circular lower cross section, and an inner housing that is disposed inside of a lower portion of the outer housing and that has a cylindrical shape with an opening formed at its side surface, the inner housing being rotatably supported in the lower portion of the outer housing, and at the opening a bridging portion being formed along a longitudinal direction of the inner housing.