A cleaning unit provided in a xerographic image forming apparatus removes residual toner from a photosensitive belt after a transfer process for transferring a developed image from the photosensitive belt to a recording sheet. The cleaning unit includes a cleaning blade for scraping the residual toner from the photosensitive belt, and a housing for storing the residual toner scraped by the cleaning blade. The cleaning blade has a slanting surface formed between a top surface of the cleaning blade and an end of the cleaning blade, the slanting blade slanting from the top surface toward the end of the cleaning blade so as to be inclined at a predetermined angle with respect to the top surface. The developer scraped by the cleaning blade is entered in the housing via the slanting surface and the top surface of the cleaning blade. The cleaning unit further includes a sweeping plate for feeding the residual toner scraped from the photosensitive belt by the cleaning blade into the housing, via a top surface of the cleaning blade.