The present invention provides a photothermographic material having, on one side of a support, an image forming layer including at least a photosensitive silver halide, a non-photosensitive organic silver salt, a reducing agent for the organic silver salt, and a binder, and at least one non-photosensitive layer and, on the other side of the support, a non-photosensitive back layer, wherein a total amount of ammonia contained in the two sides is from 5.times.10.sup.-4 mol/m.sup.2 to 2.times.10.sup.-2 mol/m.sup.2, and a molar ratio (A2/A1) of an ammonia content of the non-photosensitive back layer (A2) to an ammonia content of the layer on the image forming layer side (A1) is from 0.3 to 5.0; or a photothermographic material according to the above, wherein the non-photosensitive back layer includes an ammonium salt, and an ammonia content of the non-photosensitive back layer is from 2 mg/m.sup.2 to 100 mg/m.sup.2.