An image forming apparatus includes: an image bearing member for bearing a toner image; a belt for transferring the toner image from the image bearing member onto a transfer material; an electric power supplying device, contacted to the belt, to which a voltage is to be applied, wherein the electric power supplying device includes an erected fiber portion formed with a plurality of electroconductive erected fibers contacted to the belt; a power source; and a contact member, connected to the electric power supplying device, for applying the voltage from the power source to the electric power supplying device. The electric power supplying device includes a welded portion formed by heat aggregation of a part of the erected fiber portion, and the contact member is connected to the welded portion.