An image forming apparatus including: a plurality of image forming units each having at least an electrophotographic photoreceptor, a latent image forming device to form an electrostatic latent image on the electrophotographic photoreceptor, a developing device to develop the electrostatic latent image with toner to form visible toner image on the electrophotographic photoreceptor, a transferring device to transfer the visible toner image onto a toner image receiving member and a cleaning device to remove the toner remaining on the electrophotographic photoreceptor after transferring the visible toner image by the transferring device, wherein the plurality of image forming units are arranged so as to transfer and pile up the visible toner images successively onto said other material to form a toner image, and wherein the toners used in each of the image forming units have different colors and the turbidity of less than 60, and the difference of the turbidity of the toner having the highest turbidity and that of the toner having the lowest turbidity among the toners is 5 to 45.