To lessen the back scattering in radiation image recording of a radiation image information recorder/reader using a stimulable phosphor sheet.

This radiation image information recorder/reader has an image recording section 10 which accumulates and records the radiation image information of a subject 11 to the stimulable phosphor sheet 2 by irradiating the sheet 2 with radiations 13 transmitted through the subject 11 and a reading unit 21 for reading the radiation image information from the stimulable phosphor sheet 2 recorded with this information. The surface side of the stimulable phosphor sheet 2 opposite to the surface irradiated with the radiations is provided with a back scattering preventive means 40 which consists of flexible sheet 41 and plural heavy metal-containing materials 42 disposed on this sheet 41 and is movable between a position where the means faces the sheet and a position where the means is retreated from this position.