The invention provides a photothermographic material having, on both sides
of a support, an image forming layer including at least a photosensitive
silver halide, a non-photosensitive organic silver salt, a reducing
agent, and a binder, which is to be exposed with X-rays using a
fluorescent intensifying screen, wherein (1) a coating amount of the
photosensitive silver halide per one side is from 0.01 g/m.sup.2 to 0.45
g/m.sup.2 in terms of silver amount; and (2) a crossover (%) is 30% or
more, or when parallel light having the same wavelength as a main
emission peak wavelength of the fluorescent intensifying screen is
incident perpendicular to the surface of the photothermographic material,
the parallel light component of transmitted light comprises 5% or more of
the incident light. A photothermographic material for medical use having
high sensitivity and high image quality is provided.