An image forming apparatus includes a plurality of image forming portions, an intermediate transfer belt, a belt displacement detector, an attraction force changer, and a controller. The intermediate transfer belt is an endless belt wound around drive and driven rollers. The belt displacement detector detects displacement of the intermediate transfer belt in a rotation axis direction of the driven roller. The attraction force changer is operable to change electrostatic attraction force of the driven roller with respect to the intermediate transfer belt exerted on each of opposite end sides of the driven roller in the rotation axis direction thereof. When the belt displacement detector detects displacement of the intermediate transfer belt, the controller makes the attraction force changer increase the electrostatic attraction force of the driven roller with respect to the intermediate transfer belt exerted on a side opposite to a side toward which the displacement has taken place.