An image forming apparatus to form an image on a recording material includes a photosensitive member, an exposure device to form a latent image on the photosensitive member, a tubular body defining a space in which at least a part of the exposure device is contained, and a support portion that supports the exposure device and is provided along a rotation axis direction of the photosensitive member in the space of the tubular body. The image forming apparatus further includes, in the rotation axis direction, a first side plate fixed to one end portion of the tubular body, and a second side plate fixed to another end portion of the tubular body. One support portion end portion in the rotation axis direction is fixed to the first side plate, and another support portion end portion in the rotation axis direction is fixed to the second side plate.