A developing device for developing an electrostatic latent image, which is formed on an image-bearing body, with a developer which includes a toner and a carrier, the developing device comprises a developing roll, which includes a fixed magnet at an interior portion and a rotatable sleeve at an outer side thereof, and which is disposed to oppose the image-bearing body, rotates while carrying the developer, and conveys the developer to a developing region in a direction opposite to a direction of progress of the image-bearing body for developing the electrostatic latent image formed on the image-bearing body, wherein the developing roll includes a magnetic pole which includes, in a circumferential direction of the developing roll, at least two magnetic flux density peaks with the same polarity in the developing region, one of the magnetic flux density peaks opposing an end portion of the developing region at a downstream side in the direction of progress of the image-bearing body.