Abstract: When the laser-stimulable phosphor plate of an information reading apparatus for radiation image is constituted of CsI as the base and 0.0003 to 0.03% in atomic ratio of Na, the output signal of the information reading apparatus can be increased and the decay time thereof can be shortened. When output signals are produced by detecting fluorescence emitted from a fluoroscopic plate disposed in confrontation with the laser-stimulable phosphor plate, there is provided an information reading apparatus for radiation image having an improved S/N ratio and a high efficiency of taking in laser-stimulated luminescence. Further, instead of Na or together with Na, there may be added at least one element selected from the group consisting of Li, K, Rb, Cu, Au, Be, Mg, Ca, Sr, Ba, Zn, Cd, Hg, B, Al, Ga, In, Tl, Sc, Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Si, Ti, Zr, Ge, Sn, Pb, As, Sb, and Bi. In this case, the total content of these elements is set to be 0.00001 to 1% in atomic ratio.