An image forming apparatus includes an electrostatic latent image carrier. A plurality of development units each accommodate a toner and are held by a development unit holder. A control unit controls the development unit holder and selectively changes over the development unit used in development. An identifying device identifies color information on the toner. The development unit holder holds at least two development units accommodating toner of a same color. The control unit identifies development units of the same color based on the color information identified by the identifying device, and controls the development unit holder to effect monochrome development by using the at least two development units.