<p>An image forming apparatus is constituted by an image-bearing member for bearing a latent image, and a developing apparatus for developing the latent image. The developing apparatus is constituted by a developer container for containing a toner, and a developer-carrying member for carrying and conveying the toner contained in the developer container to a developing zone opposite the image-bearing member. The developer-carrying member is provided with a coating layer containing electroconductive fine particles. A developer suitable for use in the above developing apparatus is given by a toner, which comprises a binder resin composition which contains 10 - 70 wt. % of a THF (tetrahydrofuran)-insoluble content and the remainder of a THF-soluble content including a component with a molecular weight of 10000 or below on a GPC (gel permeation chromatography) chromatogram of the THF-soluble content constituting 10 - 50 wt. % of the binder resin.</p>