A developing device includes a developer bearing member including an internal magnetic field generating device and configured such that a surface thereof moves to carry and convey a developer including toner and carrier. A developer regulating member regulates a quantity of the developer carried and conveyed by the developer bearing member toward a developing area, and a developer accommodating unit accommodates the developer regulated to be conveyed toward the developing area by the developer regulating member. A toner accommodating unit includes a toner supplying opening opposing a surface of the developer bearing surface of the developer bearing member at a position adjacent to and upstream of the developer accommodating unit in a developer conveying direction. The toner in the toner accommodating unit is taken into the developer on the developer bearing member based on a toner density of the developer on the developer bearing member by a movement of the developer with a conveyance of the developer on the developer bearing member. The developing device further includes a peeling off member that opposes, without contacting, a surface of the developer bearing member in the developer accommodating unit so as to peel off an upper layer part of the developer carried and conveyed by the developer bearing member.