A color electrophotographic apparatus having a photosensitive member, an exposing device for forming an electrostatic latent image on the photosensitive member, four developing devices which attach toner on the photosensitive member and form a toner image and a transfer member for transferring the toner image onto a printing medium. The four developing devices include respectively a developing device for a yellow image, a magenta image, cyan image, and a black image. Each developing device includes a toner storing chamber for storing toner of a nonmagnetic one-component developer, a toner carrying member for forming a toner layer of the toner, a regulating member for regulating an amount of toner attached to the toner carrying member, a toner recovery chamber having an agitating member for agitating recovered toner, and a separating member for separating a toner supply chamber for the toner carrying member from the toner recovery chamber.