An electrostatic latent image developing apparatus has a developing sleeve, an agitating roller rotatable in the same direction as the developing sleeve and a magnetic device fixedly provided within the developing sleeve and having a plurality of N and S poles which include auxiliary poles of the same polarity adjacent to each other circumferentially of the sleeve and opposed to the agitating roller. A developer restraining plate between the developing sleeve and the agitating roller has a first guide surface for guiding the developer supplied by the agitating roller and a second guide surface for limiting the developer used from moving toward the sleeve portion to which the developer is supplied by the agitating roller.