Abstract: Disclosed is a color diffusion transfer photographic film unit improved in separability and light fastness. It comprises (1) a light sensitive sheet having an image receiving layer, a white reflective layer, a shading layer and at least one silver halide emulsion layer having at least one dye image forming substance, which layers are formed on a transparent support, (2) a transparent cover sheet comprising a neutralization layer and a neutralization timing layer, which layers are formed on a transparent support, and (3) a shading alkali treating composition developed between the light sensitive sheet and the transparent cover sheet. Further, the image receiving layer contains a hydrazine derivative represented by the following general formula (I): ##STR1## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.