A toner cartridge includes a toner supply pipe and a first shutter. The toner supply pipe has a toner supply opening. When the toner cartridge is mounted onto a main unit, the toner supply pipe moves through an insertion opening from an outside position at which the toner supply opening is located outside a developing frame to an inside position at which the toner supply opening is located inside the developing frame. The first shutter is provided at the toner supply pipe. The first shutter moves relative to the toner supply pipe between an open position at which the toner supply opening is opened and a closed position at which the toner supply opening is closed. The first shutter moves relative to the toner supply pipe from the closed position to the open position in a state where the toner supply pipe is located at the inside position.