a process cartridge is detachably mountable to a main assembly of an electrophotographic image forming apparatus . the cartridge includes an electrophotographic photosensitive drum , a drum unit supporting the drum , a developing unit supporting a developing roller and swingably coupled with the drum unit , drum and developing roller rotating force receiving portions first and second positionable portions positioned at first and second main assembly side positioning portion by contacting to the first main assembly side positioning portions by contacting by the urging force of first and second main assembly side urging members , a developing device spacing force receiving portion , first and second cartridge side rotation regulating portions for limiting rotation of the drum unit by abutting first and second main assembly side rotation regulating portions , when the drum and developing roller rotating force receiving portions receive the rotating forces or when the developing device spacing force receiving portion receives the urging force from the main assembly .