A developer container, which includes an opening and is configured to store developer therein, includes a developer conveyance plate configured to convey the developer. The developer conveyance plate includes a vibration target unit configured to receive a vibration, and conveys the developer in a first direction in which the developer is conveyed toward an opening side, and in a second direction perpendicular to the first direction. The developer is conveyed by the vibration transmitted from the vibration target unit with use of a resultant force generated by adding a conveyance component in the first direction and a conveyance component in the second direction. A maximum acceleration a1 (max) in the first direction that is provided to the developer conveyance plate by the vibration transmitted from the vibration target unit is set to a lower acceleration than a maximum acceleration a2 (max) in an opposite direction from the first direction.