A developing cartridge includes a lever, an urging member, a first gear, a second gear, and a protrusion rotatable together therewith. The lever is movable between a first position and a second position. The urging member urges the lever toward the first position. The first gear includes first and second gear portions. The second gear portion has an addendum circle greater than that of the first gear portion. The second gear includes a third gear portion engageable with the first gear portion and a fourth gear portion engageable with the second gear portion. The fourth gear portion has an addendum circle smaller than that of the third gear portion. In a case where the second gear rotates while engaging with the fourth gear portion, the protrusion contacts the lever to move the lever from the first position to the second position against urging force of the urging member.