According to one embodiment of the present invention, an erasing apparatus includes a used sheet stacking tray, an image erasing unit, a stand-by tray, a stand-by tray driving unit, and an erased sheet stacking tray. The used sheet stacking tray stacks thereon a used sheet on which an image is formed using an erasable colorant of which a color is erased by a predetermined heating process. The image erasing unit performs the heating for the used sheet which is received one by one from the used sheet stacking tray and discharges an erased sheet from which the image formed on the used sheet is erased. The stand-by tray has a mechanism which can be driven in a predetermined direction and places thereon the erased sheet discharged by the image erasing unit. The stand-by tray driving unit drives the stand-by tray and enables the erased sheet to free-drop. The erased sheet stacking tray is disposed under the stand-by tray and stacks thereon the erased sheet which free-drops from the stand-by tray.