An image forming unit including a photosensitive member including a gear portion on a one end side of the photosensitive member in a rotational axis direction, a roller that comes in contact with thephotosensitive member, a bearing member that rotatably supports the roller, and an elastic member that urges the bearing member. In the image forming unit, directions of moments about a rotational axis of the roller acting on the bearing member disposed on the one end side of the photosensitive member in the rotational axis direction are the same in a case in which the roller is rotated and in a case in which the roller is stopped.