A device for erasing an image on a sheet according to an embodiment includes a reading unit that reads an image formed on the sheet. An erasing unit erases the image formed on the sheet by heating the sheet. A conveyance path for the sheet between the reading unit and the erasing unit is formed guide plates arranged in an opposed manner. A cooling unit cools the sheet which passes through the conveyance path and includes at least one fan that supplies cooling air generally along a sheet conveying direction. A plurality of slits is formed in each of the guide plates such that cooling air from the at least one fan flows through the slits into the conveyance path.