To obtain a developing device which regulates the amount of developer conveyed to a developing part by using a regulation roller, and which surely prevents fusion or the like of toner by suppressing the temperature rise of the regulation roller without causing the increase in the scale of the developing device.

A cleaning blade 5 is brought into press-contact with the regulation roller 2 so as to scrape off the developer or the like adhering to the surface of the regulation roller 2. A Peltier element 6 is attached to the back side of the cleaning blade 5 so as to cool the regulation roller 2 via the cleaning blade 5.