An image forming apparatus includes at least one first image carrier that carries a chromatic color toner image formed thereon, a second image carrier that carries a black toner image formed thereon, at least one first gear that rotates to drive the first image carrier to rotate, a second gear that rotates to drive the second image carrier to rotate, and a control device that controls respective rotation stop-positions of the first and second gears. The control device controls the first gear and the second gear to stop rotating at positions different from rotation start-positions of the first gear and the second gear, respectively, while maintaining a predetermined phase relation between the first gear and the second gear in a color mode, and the control device controls the second gear to stop rotating at a position substantially equal to a rotation start-position of the second gear in a monochrome mode.