A developing cartridge comprising: a housing (11, 211) configured to accommodate toner therein, the housing having an outer surface (11C, 211C); a developing roller rotatable about a first axis extending in an axial direction; a first helical gear (22, 26) positioned at the outer surface (11C, 211C) and rotatable about a second axis (22X, 26X) extending in the axial direction, the first helical gear being rotatable in accordance with rotation of the developing roller; a second helical gear (24, 225) positioned at the outer surface (11C, 211C) and rotatable in a first rotational direction (D1, D3) and a second rotational direction (D2, D4) opposite to the first rotational direction about a third axis (13X, 14X) extending in the axial direction, the second helical gear being movable in the axial direction between a first position and a second position positioned closer to the outer surface (11C, 211C) than the first position is to the outer surface (11C, 211C), the second gear being moved to the first position by a first thrust force (F1, F3) generated by the meshing engagement between the first helical gear (22, 26) and the second helical gear (24, 225) in a case where the second helical gear (24, 225) rotates in the first rotational direction (D1, D3), the second helical gear (24, 225) being moved to the second position by a second thrust force (F2, F4) generated by the meshing engagement between the first helical gear (22, 26) and the second helical gear (24, 225) in a case where the second helical gear (24, 225) rotates in the second rotational direction (D2, D4); and an engaging member (50, 250A) rotatable about the third axis (13X, 14X) together with the second helical gear (24, 225) and movable in the axial direction together with the second helical gear (24, 225), the second helical gear (24, 225) being rotatable in the first rotational direction (D1, D3) in accordance with the rotation of the first helical gear (22, 26) in a case where the second helical gear is at the first position, the engaging member (50, 250A) being engaged with a part of the outer surface (11C, 211C) to terminate the rotation of the second helical gear (24, 225) in the second rotational direction (D2, D4) in a case where the second helical gear (24, 225) is at the second position. a housing (11, 211) configured to accommodate toner therein, the housing having an outer surface (11C, 211C); a developing roller rotatable about a first axis extending in an axial direction; a first helical gear (22, 26) positioned at the outer surface (11C, 211C) and rotatable about a second axis (22X, 26X) extending in the axial direction, the first helical gear being rotatable in accordance with rotation of the developing roller; a second helical gear (24, 225) positioned at the outer surface (11C, 211C) and rotatable in a first rotational direction (D1, D3) and a second rotational direction (D2, D4) opposite to the first rotational direction about a third axis (13X, 14X) extending in the axial direction, the second helical gear being movable in the axial direction between a first position and a second position positioned closer to the outer surface (11C, 211C) than the first position is to the outer surface (11C, 211C), the second gear being moved to the first position by a first thrust force (F1, F3) generated by the meshing engagement between the first helical gear (22, 26) and the second helical gear (24, 225) in a case where the second helical gear (24, 225) rotates in the first rotational direction (D1, D3), the second helical gear (24, 225) being moved to the second position by a second thrust force (F2, F4) generated by the meshing engagement between the first helical gear (22, 26) and the second helical gear (24, 225) in a case where the second helical gear (24, 225) rotates in the second rotational direction (D2, D4); and an engaging member (50, 250A) rotatable about the third axis (13X, 14X) together with the second helical gear (24, 225) and movable in the axial direction together with the second helical gear (24, 225), the second helical gear (24, 225) being rotatable in the first rotational direction (D1, D3) in accordance with the rotation of the first helical gear (22, 26) in a case where the second helical gear is at the first position, the engaging member (50, 250A) being engaged with a part of the outer surface (11C, 211C) to terminate the rotation of the second helical gear (24, 225) in the second rotational direction (D2, D4) in a case where the second helical gear (24, 225) is at the second position.