A developing cartridge capable of being attached to and detached from a body of an image forming apparatus, the body having an image carrier and a restricting portion (114, 115), the developing cartridge comprising: a developer carrier including a contact portion configured to make contact with the image carrier provided outside the developing cartridge; a first unit (37, 38) configured to be fixed to the body when the developing cartridge is in a predetermined attachment position in the body; and characterised by a second unit supporting the developer carrier, the second unit being movable with respect to the first unit (37, 38) so that the developer carrier is capable of making contact with and separating from the image carrier when the developing cartridge is in the predetermined attachment position, wherein the first unit (37, 38) is positioned at an end portion of the second unit in a direction of a central axis of rotation of the developer carrier, wherein the developing cartridge is configured to be guided up to the predetermined attachment position in the direction of the central axis of rotation of the developer carrier, wherein the developer carrier is movable with respect to the first unit (37, 38) in a moving direction different from the direction of the central axis of rotation of the developer carrier, with movement of the second unit with respect to the first unit (37, 38), and wherein the second unit includes a protrusion portion as a restricted portion (31g, 31h) extending in the direction of the central axis of rotation of the developer carrier, the restricted portion (31g, 31h) being (i) configured to come into contact with the restricting portion (114, 115) when the developing cartridge is guided up in the direction of the central axis of rotation of the developer carrier to the predetermined attachment position and has not reached the predetermined attachment position so as to prevent the developer carrier from making contact with the image carrier, and (ii) configured not to come into contact with the restricting portion (114, 115) so as to allow the developer carrier to move in the moving direction and make contact with the image carrier when the developing cartridge is in the predetermined attachment position. a developer carrier including a contact portion configured to make contact with the image carrier provided outside the developing cartridge; a first unit (37, 38) configured to be fixed to the body when the developing cartridge is in a predetermined attachment position in the body; and characterised by a second unit supporting the developer carrier, the second unit being movable with respect to the first unit (37, 38) so that the developer carrier is capable of making contact with and separating from the image carrier when the developing cartridge is in the predetermined attachment position, wherein the first unit (37, 38) is positioned at an end portion of the second unit in a direction of a central axis of rotation of the developer carrier, wherein the developing cartridge is configured to be guided up to the predetermined attachment position in the direction of the central axis of rotation of the developer carrier, wherein the developer carrier is movable with respect to the first unit (37, 38) in a moving direction different from the direction of the central axis of rotation of the developer carrier, with movement of the second unit with respect to the first unit (37, 38), and wherein the second unit includes a protrusion portion as a restricted portion (31g, 31h) extending in the direction of the central axis of rotation of the developer carrier, the restricted portion (31g, 31h) being (i) configured to come into contact with the restricting portion (114, 115) when the developing cartridge is guided up in the direction of the central axis of rotation of the developer carrier to the predetermined attachment position and has not reached the predetermined attachment position so as to prevent the developer carrier from making contact with the image carrier, and (ii) configured not to come into contact with the restricting portion (114, 115) so as to allow the developer carrier to move in the moving direction and make contact with the image carrier when the developing cartridge is in the predetermined attachment position.