A toner image forming method is disclosed. In the method a photoreceptor having a shorter circumferene than length of a toner image to be transferred is used. The photoreceptor is exposed with an exposing light according to an image information to form a latent image and is processed with a step of removing residual toner particles on a non-image portion on the photoreceptor and developing a latent image on the photoreceptor with toner particles at a same time or successively to form the toner image. The toner particles have a specral characteristics which allows tho exposing light to pass through the toner particles. The method allows to provide a compact copying apparatus.