A process cartridge for an image forming apparatus includes a cleaning unit for removing waste toner remaining on a surface of a photosensitive drum, and a cleaning frame for storing the waste toner removed by the cleaning unit. The cleaning unit includes a bent portion adapted to bend in a direction opposite to the photosensitive drum and be disposed at a site other than that in which the waste toner is accumulated. The cleaning unit further includes a cleaning blade for contacting with the surface of the photosensitive drum to remove the waste toner remaining thereon in response to rotation of the photosensitive drum, and a cleaning support member for supporting the cleaning blade.