An apparatus for erasing the fog developing in a stimulable phosphor sheet used for a radiation image recording and reproducing system in which a radiation image is once recorded in the stimulable phosphor sheet and then read out and reproduced on a recording material. The apparatus is arranged so that stimulable phosphor sheets are taken up one at a time out of their reservoir and each is loaded into a cassette used for the recording of a radiation image. It comprises a light source for erasing the fog, which is provided between the aperture of the reservoir from which the stimulable phosphor sheets are taken up and the section at which the sheets are loaded into the cassettes.