There is provided a cleaning unit for removing residual toner present on the periphery of a photoconductive drum (42) after toner image transfer, which includes: a main blade (105) for scraping the toner from the surface of the photoconductive drum (42); and a cleaning roller (107) disposed below the main blade (105) and abutting against the periphery of the photoconductive drum (42). The inner space of the cleaning housing (101) is divided into a cleaning chamber (103) and a toner storage (104) by a separator plate (102). A spacing (S) between the lower end (102a) of the separator plate (102) and the periphery of the cleaning roller (107) is adjusted to preferably 1mm to 2mm, more preferably 1.3mm to 1.5mm. By thus adjusting the spacing (S), the toner is compressed when passing through the spacing and, hence, the toner transportation pressure is increased.