To provide a color diffusion/transfer film unit in which the progression of transfer is quick, and the whiteness of a white background part is high.

The diffusion/transfer film unit includes: a photosensitive sheet which has, on the surface of a transparent support, an image receiving layer, a white light diffusion layer containing titanium dioxide particulates dispersed in gelatin, a light shielding layer, and one or more silver halide emulsion layers combined with at least one pigment image forming substance; a transparent cover sheet which has, on the surface of a support, a neutralization layer and a neutralization timing layer; and an alkali treatment composition containing a light shielding agent developed after exposure between the photosensitive sheet and the transparent cover sheet, and they are arranged so as to be exposed through the transparent cover sheet, and in the white light diffusion layer positioned between the image receiving layer and the light shielding layer. The mass ratio of the titanium dioxide/gelatin is ≤10, the content of the gelatin is ≤1.7 g/m2, and the mass ratio between the titanium dioxide particulates and spacer particulates is 10:1 to 10:5.