An image forming apparatus includes a main body; a process cartridge being detachably mounted to the main body along a direction perpendicular to a rotational axis direction, the process cartridge including a photosensitive member, and a charger facing a surface of the photosensitive member; and an exposure device including a plurality of light emitting devices arranged along the rotational axis direction, and a facing part. The facing part is a part of the exposure device that is positioned closest to the photosensitive member and faces the surface of the photosensitive member when seen from the rotational axis direction, at a state in which the process cartridge is mounted, and the charger is positioned at an opposite side of the exposure device with respect to a second line which is parallel with the mounting direction and passes the facing part when seen from the rotational axis direction.