A developing apparatus supplies a developer from a developing roller to an image-bearing body that bears an electrostatic latent image thereon. A toner-supplying roller is rotatably supported to oppose the developing roller. A rotating body has recesses formed in its surface, opposing the developer-bearing member. The toner-supplying roller and the rotating body rotate in opposite directions and at different circumferential speeds. The rotating body is formed of a foamed material having cells formed in and open to a surface of the rotating body, the cells having a cell size in the range of 10 to 40 cells/inch. The toner-supplying roller and the rotating body rotate at circumferential speeds such that a ratio between the circumferential speeds is in the range of 1 to 2.5. The rotating body and toner-supplying roller may have a diameter that varies along the length.