An electrostatic latent image is formed on an image carrier. A developer includes a container containing toner, a first roller facing the image carrier and rotated to cause the toner to adhere onto the image carrier to develop the electrostatic latent image as a toner image, a second roller supplying the toner from the container to the first roller, and a control member extending in an axial direction of the first roller and brought into contact with the first roller. A tip end edge of the control member is situated in an upstream side of a contact line that extends in the axial direction so as to include at least one contact point between the control member and the first roller, relative to a rotating direction of the first roller. A distance between the tip end edge and the contact line is not constant relative to the axial direction.