An electrophotographic image forming apparatus on which a process cartridge is detachably mountable forms an image on a recording medium, and has a main body electrical contact electrically connected to a cartridge electrical contact when the cartridge is mounted on an apparatus main body, an electrically grounded electrically conductive discharge preventing member for effecting discharge between it and a charged foreign substance to thereby prevent discharge from occurring between the foreign substance and the main body electrical contact when the foreign substance has entered the apparatus main body on which the process cartridge is not mounted. The discharge preventing member is movable between a first position located in the entry route of the cartridge and a second position retracted from the first position and located outside the entry route. The apparatus also has an actuating member for moving the discharge preventing member from the first to the second position.