Abstract: A developing device includes an agitating transport device, a density detecting device, and an attracting device. The agitating transport device has a transport path and transports developer including a magnetic carrier while agitating the developer. The density detecting device detects density of the developer in the transport path of the agitating transport device. The attracting device is provided in the agitating transport device and has magnetic poles of one and another polarities exposed to the transport path facing the density detecting device so as to attract the developer by a magnetic force.