A developing device includes a developing housing, a developing unit, and a transport unit. The developing housing includes a container chamber containing a developer. The developing unit rotates around a first rotation axis while carrying the developer on a surface thereof to deliver the developer. At least a partial region of the developing unit is exposed from the developing housing in a developing region below the first rotation axis such that the developing unit faces an image carrier. The developing unit develops an electrostatic latent image. The transport unit is disposed in the container chamber. The transport unit rotates around a second rotation axis to transport the developer. A part of an inner wall surface of the container chamber on a developer lifting side in which the surface of the developing unit moves toward the transport unit is located between a first plane and a second plane.