Method for obtaining a colored copied image by repeating a cycle consisting of the process of forming an electrostatic latent image on an electrophotographic copying material having a photoconductive layer, the process of transferring said electrostatic latent image onto a transfer sheet having a dielectric layer and the process of developing the thus transferred electrostatic latent image for each primary color of the colored original image, an improved method of forming a colored copied image free of fog which method comprises employing a transfer sheet having a dielectric layer containing a photoconductive substance and interposing an additional process of applying active radiant rays to the whole surface of said dielectric layer upon which the image is developed between said cycles, and a transfer sheet useful in the method.