A developing device is provided with: a developer containing section that is for containing a developer and that has a predetermined coefficient of thermal expansion; a developing roller for bearing the developer contained in the developer containing section; a roller-supporting member that is for rotatably supporting the developing roller, that has a coefficient of thermal expansion which is different from the coefficient of thermal expansion of the developer containing section, and that is structured by connecting at least three members; and a gap for preventing the roller-supporting member and the developer containing section from interfering with one another when the roller-supporting member and the developer containing section expand/contract due to a change in temperature.