In a radiation-image conversion panel, a fluorescent layer containing a
phosphor and a protective layer are formed on a support in this order.
The protective layer has a water-vapor transmission rate of 1
g/m.sup.2/24 h or lower at 40.degree. C. and a reflectance of 3% or lower
at a wavelength of light emitted from the phosphor. In addition, the
protective layer may be obtained by attaching a removable film to a thin
transparent film so as to produce a laminated film, forming a
vapor-barrier layer on an exposed surface of the thin transparent film by
vacuum deposition so as to produce a moisture-resistant film, placing the
moisture-resistant film on the fluorescent layer, and removing the
removable film from the moisture-resistant film.