An image erasing apparatus, comprising: a sheet supply portion for supplying a sheet; an ejector (19, 20) for ejecting the sheet; a first conveying path to form a conveying path from the sheet supply portion toward the ejector to convey the sheet in a sheet conveying direction; a reader arranged on the first conveying path for reading an image on a surface of the sheet; a second conveying path branching from the first conveying path at a downstream side of the reader in the sheet conveying direction and merging with the first conveying path at a meeting point situated between the sheet supply portion and the reader; an erasure arranged on the second conveying path for erasing the image on the sheet formed with image erasable material; a switching portion arranged on the first conveying path at a downstream side of the reader in the sheet conveying direction to switch the sheet conveying direction to a direction of the ejector (19, 20) or to a direction of the erasure, a controller; wherein the controller is configured to accept at least one processing mode selected from at least one of a reading mode in which the reader reads the image on the sheet, an image erasing mode in which the erasure erases the image on the sheet, and a discriminating mode in which the reader reads the image on the sheet to judge whether or not the sheet is reusable; and is configured to cause the sheet to be conveyed to pass through the erasure at a first conveying speed, to cause the sheet to be conveyed to pass through the reader at a second conveying speed and to control the first conveying speed and the second conveying speed in accordance with the selected processing mode. a sheet supply portion for supplying a sheet; an ejector (19, 20) for ejecting the sheet; a first conveying path to form a conveying path from the sheet supply portion toward the ejector to convey the sheet in a sheet conveying direction; a reader arranged on the first conveying path for reading an image on a surface of the sheet; a second conveying path branching from the first conveying path at a downstream side of the reader in the sheet conveying direction and merging with the first conveying path at a meeting point situated between the sheet supply portion and the reader; an erasure arranged on the second conveying path for erasing the image on the sheet formed with image erasable material; a switching portion arranged on the first conveying path at a downstream side of the reader in the sheet conveying direction to switch the sheet conveying direction to a direction of the ejector (19, 20) or to a direction of the erasure, a controller; wherein the controller is configured to accept at least one processing mode selected from at least one of a reading mode in which the reader reads the image on the sheet, an image erasing mode in which the erasure erases the image on the sheet, and a discriminating mode in which the reader reads the image on the sheet to judge whether or not the sheet is reusable; and is configured to cause the sheet to be conveyed to pass through the erasure at a first conveying speed, to cause the sheet to be conveyed to pass through the reader at a second conveying speed and to control the first conveying speed and the second conveying speed in accordance with the selected processing mode.