A developing cartridge that can be detachably mounted to a main body of an image forming apparatus, the developing cartridge comprising: a housing including a developing chamber and a developer accommodating chamber that accommodates developer to be supplied to the developing chamber, wherein the developing chamber and the developer accommodating chamber are adjacent to each other; a developing roller, which is provided in the developing chamber, and which includes a developing roller shaft extending in a facing direction of both sidewalls of the housing; a supply roller, which is provided in the developing chamber, which includes a supply roller shaft extending in the facing direction of the both sidewalls of the housing, and which supplies the developer to the developing roller; a developing electrode, which is provided on an outer side of one sidewall of the housing, wherein the developing electrode is electrically connected to the developing roller shaft, and wherein the developing electrode includes a developing protrusion protruding in a direction parallel to the developing roller shaft at a position different from the developing roller shaft when seen from a side face; and a supply electrode, which is provided on the outer side of the one sidewall, wherein the supply electrode is electrically connected to the supply roller shaft, and wherein the supply electrode includes a supply protrusion protruding in a direction parallel to the supply roller shaft at a position different from the supply roller shaft when seen from the side face, and wherein the developing protrusion and the supply protrusion are arranged in an arrangement direction of the developing chamber and the developer accommodating chamber, the arrangement direction extending from the developing chamber to the developer accommodating chamber in the mounting direction, characterized in that the developing protrusion comprises: a parallel surface that is parallel to the arrangement direction; and a plurality of inclined surfaces (86, 87), which are contiguous with the parallel surface, wherein the inclined surfaces (86, 87) are formed on both sides, in the arrangement direction, of the parallel surface, and wherein the inclined surfaces (86, 87) are inclined with respect to the parallel surface. a housing including a developing chamber and a developer accommodating chamber that accommodates developer to be supplied to the developing chamber, wherein the developing chamber and the developer accommodating chamber are adjacent to each other; a developing roller, which is provided in the developing chamber, and which includes a developing roller shaft extending in a facing direction of both sidewalls of the housing; a supply roller, which is provided in the developing chamber, which includes a supply roller shaft extending in the facing direction of the both sidewalls of the housing, and which supplies the developer to the developing roller; a developing electrode, which is provided on an outer side of one sidewall of the housing, wherein the developing electrode is electrically connected to the developing roller shaft, and wherein the developing electrode includes a developing protrusion protruding in a direction parallel to the developing roller shaft at a position different from the developing roller shaft when seen from a side face; and wherein the developing electrode is electrically connected to the developing roller shaft, and wherein the developing electrode includes a developing protrusion protruding in a direction parallel to the developing roller shaft at a position different from the developing roller shaft when seen from a side face; and a supply electrode, which is provided on the outer side of the one sidewall, wherein the supply electrode is electrically connected to the supply roller shaft, and wherein the supply electrode includes a supply protrusion protruding in a direction parallel to the supply roller shaft at a position different from the supply roller shaft when seen from the side face, and wherein the supply electrode is electrically connected to the supply roller shaft, and wherein the supply electrode includes a supply protrusion protruding in a direction parallel to the supply roller shaft at a position different from the supply roller shaft when seen from the side face, and wherein the developing protrusion and the supply protrusion are arranged in an arrangement direction of the developing chamber and the developer accommodating chamber, the arrangement direction extending from the developing chamber to the developer accommodating chamber in the mounting direction, characterized in that a parallel surface that is parallel to the arrangement direction; and a plurality of inclined surfaces (86, 87), which are contiguous with the parallel surface, wherein the inclined surfaces (86, 87) are formed on both sides, in the arrangement direction, of the parallel surface, and wherein the inclined surfaces (86, 87) are inclined with respect to the parallel surface.