To obtain a color diffusion transfer image forming method excellent in color image density and image fastness by allowing a dye formed by reaction with the oxidized body of a specified compound to coexist with at least one kind of a specified water-soluble compound.

A dye formed by reaction with the oxidized body of a compound of formula I is allowed to coexist with at least one kind of a water-soluble compound of formula II on a substrate. In the formula I, Z is carbamoyl, acyl, alkoxycarbonyl, aryloxycarbonyl, sulfonyl or the like and Q is a group of atoms forming an unsaturated ring together with C. In the formula II, X is H, hydroxy, an aliphatic group or the like Y1 and Y2 may be the same or different and are each H or a substituent, Z1 is a simple bonding radical methylene which may have a substituent or ethylene, Z2 is methylene which may have a substituent and R1-R4 may be the same or different and are each an aliphatic group.