A process cartridge and an image forming apparatus are provided. The process cartridge is detachably mountable in an apparatus body of the image forming apparatus, and includes a plurality of photosensitive drums, a first outer side plate which is provided on one side of the photosensitive drums in an axial direction of the photosensitive drum, a second outer side plate which is provided on the other side of the photosensitive drums in the axial direction, and opposes the first outer side plate with the photosensitive drums interposed therebetween, and a plurality of input parts which are provided on ends of the photosensitive drums at the one side, respectively. An end face of each of the input parts being provided inward with respect to the outer surface of the first outer side plate.