In an image forming apparatus, a toner carrier roller rotatably mounted to a housing that stores toner rotates to convey toner to an opposed position facing a latent image carrier outside the housing. A plurality of convex sections are regularly arranged on a surface of the roller in an axial direction parallel to the rotational axis and in a circumferential direction orthogonal to the axial direction and parallel to a circumferential surface of the roller and a concave section surrounds the convex sections. A seal member abuts the surface of the roller moving from the outside toward the inside of the housing at a position downstream of the opposed position in a rotation direction of the roller to prevent toner leakage from inside the housing. The roller moves relative to the seal member in the axial direction.