A stimulable phosphor sheet preferably employable in autoradiography which comprises a substrate, a phosphor layer being provided on the substrate and comprising a stimulable phosphor dispersed in a binder, and a protective layer provided on the phosphor layer, characterized in that the surface of the protective layer is hydrophilic.The surface of the protective layer can be made hydrophilic by hydrophilic processing applied thereto or provision of a hydrophilic layer thereon.