A process cartridge detachably mountable to a main assembly of an electrophotographic image forming apparatus, includes an electrophotographic photosensitive drum, a developing roller for developing a latent image formed on the drum while in contact with the drum, a drum unit supporting the drum, a developing unit supporting the developing roller and movable with the drum unit between contact and spaced apart positions in which the developing roller and the drum contact or are spaced from each other, a drum driving force receiving portion, a movable member to move the developing unit between the contact position and the spaced position, and a movable member driving force receiving portion provided for receiving, from the main assembly, a movable member driving force for moving the movable member when the process cartridge is mounted in the main assembly.