An image forming apparatus comprising: colored toner image forming devices (Pa, Pb, Pc, Pd) each for forming an electrostatic image and developing the electrostatic image by using non-magnetic colored toner (C, M, Y, K) and a magnetic carrier for the colored toner (C, M, Y, K) to form a colored toner image, the colored toners (C, M, Y, K) being different from each other, wherein each of the colored toner image forming devices (Pa, Pb, Pc, Pd) includes a corresponding one of developing devices (4a, 4b, 4c, 4d) filled with the colored toner (C, M, Y, K) and arranged to provide the colored toner (C, M, Y, K) for developing the electrostatic image; a transparent toner image forming device (Pe) for forming an electrostatic image and developing the electrostatic image by using non-magnetic transparent toner and a magnetic carrier for the transparent toner to form a transparent toner image, wherein the transparent toner image forming device (Pe) includes a developing device filled with the transparent toner and arranged to provide the transparent toner for developing the electrostatic image; and a transfer device for superimposing and transferring the colored toner images and the transparent toner image on a transfer medium, characterized in that a base material of the transparent toner has the same material as that of each of the colored toners (C, M, Y, K), and a volume average particle diameter of the magnetic carrier for the transparent toner is larger than a volume average particle diameter of the magnetic carrier for the colored toners (C, M, Y, K) so that an absolute value of a charge amount of the transparent toner per unit weight is smaller than an absolute value of a charge amount of each of the colored toners (C, M, Y, K) per unit weight. colored toner image forming devices (Pa, Pb, Pc, Pd) each for forming an electrostatic image and developing the electrostatic image by using non-magnetic colored toner (C, M, Y, K) and a magnetic carrier for the colored toner (C, M, Y, K) to form a colored toner image, the colored toners (C, M, Y, K) being different from each other, wherein each of the colored toner image forming devices (Pa, Pb, Pc, Pd) includes a corresponding one of developing devices (4a, 4b, 4c, 4d) filled with the colored toner (C, M, Y, K) and arranged to provide the colored toner (C, M, Y, K) for developing the electrostatic image; a transparent toner image forming device (Pe) for forming an electrostatic image and developing the electrostatic image by using non-magnetic transparent toner and a magnetic carrier for the transparent toner to form a transparent toner image, wherein the transparent toner image forming device (Pe) includes a developing device filled with the transparent toner and arranged to provide the transparent toner for developing the electrostatic image; and a transfer device for superimposing and transferring the colored toner images and the transparent toner image on a transfer medium, characterized in that a base material of the transparent toner has the same material as that of each of the colored toners (C, M, Y, K), and a volume average particle diameter of the magnetic carrier for the transparent toner is larger than a volume average particle diameter of the magnetic carrier for the colored toners (C, M, Y, K) so that an absolute value of a charge amount of the transparent toner per unit weight is smaller than an absolute value of a charge amount of each of the colored toners (C, M, Y, K) per unit weight.