The invention relates to a developing cartridge and a using method of the developing cartridge. The developing cartridge is detachably mounted inside imaging equipment, and comprises a developing cartridge main body and a power transmission device positioned at one longitudinal tail end of the developing cartridge main body; the power transmission device comprises a power receiving assembly and adrive gear combined with the power receiving assembly; the drive gear is fixedly mounted inside the developing cartridge main body in advance; and before the developing cartridge is mounted to the imaging equipment, the power receiving assembly is mutually separated from the developing cartridge main body.