In a developing apparatus, the interior of a case is divided into a first space positioned on a developer supply side for the supply of a developer to an image bearing member and a second space which is supplied with a replenishing toner, first and second agitating members are included and are adapted to be rotated to agitate and convey the developer are disposed within the first and second spaces, respectively, and a screw member is provided having n threads (n.gtoreq.2) is used as the first agitating member disposed in the first space, and a screw member having (n-x) threads (x.gtoreq.0) is used as the second agitating member disposed in the second space.