In a radiation image read-out apparatus, a stimulable phosphor sheet storing thereon a radiation image is exposed to stimulating light and stimulated emission emitted from the stimulable phosphor sheet upon stimulation by the stimulating light is detected and an image signal representing the radiation image stored on the stimulable phosphor sheet is obtained by photoelectrically converting the stimulated emission. A read-out system includes an array of a plurality of read-out heads, each including a stimulating light source which projects the stimulating light onto the stimulable phosphor sheet and a photodetector which detects the stimulated emission. A conveyor system conveys the stimulable phosphor sheet and the read-out system relative to each other in a direction intersecting the direction of the array of the read-out heads.