An image forming apparatus includes: a photoconductive drum; a mixer which stirs a developer; and a developing roller which has plural magnets to supply the stirred developer to the photoconductive drum, and a separation pole that is a magnet arranged opposite the photoconductive drum in relation to a rotational center axis and separating the developer supplied to the photoconductive drum, and which is arranged in a way that a vertical first tangential line on the separation pole side is located outward to the separation pole side from an outer circumference of the mixer.