An image forming apparatus having an image carrier for forming an electrostatic latent image and a developing unit for developing the electrostatic latent image with a two-component developing agent, the developing unit includes: a developing agent carrier for developing the electrostatic latent image to form a visible image, having inside thereof a development main magnetic pole for forming a bristle of a magnetic brush; and a plurality of magnetic poles for conveying the developing agent, wherein the developing unit performs a counter type contact developing method, and wherein, a development area is formed so that, a contact width of the bristle of the magnetic brush is 70% or less with respect to a development width, and a center position of the contact width is positioned on an upstream side with respect to a center position of the development width in a rotation direction of the image carrier.