A process cartridge includes (a) an image carrier for carrying a developer image; (b) a transfer roller for transferring the developer image onto a recording medium; (c) a winding preventer for preventing the recording medium from winding around the transfer roller; and (d) a cover which covers the transfer roller and which has an opposed surface opposed to the transfer roller. The winding preventer has a contact surface extending from the opposed surface toward the transfer roller, such that a leading edge of the recording medium is held in contact with the contact surface when the recording medium is pulled into between an outer circumferential surface of the transfer roller and the opposed surface of the cover. The opposed surface includes an immediately upstream portion which is immediately upstream of the contact surface as seen in a rotational direction of the transfer roller. An angle formed between the contact surface and the immediately upstream portion is acute. Also disclosed is a process cartridge that includes the winding preventer.