The present invention provides a photothermographic material, having a
support and an image-forming layer containing a photosensitive silver
halide, a non-photosensitive organic silver salt, and a reducer for the
organic silver salt on at least one surface of the support, wherein the
image-forming layer contains a hydrophilic polymer which has a vinyl
monomer unit containing a quaternary nitrogen atom-containing group or a
nitrogen-containing heterocyclic group.