An image forming apparatus includes an image bearing member for bearing an electrostatic latent image; a developing device including a developer carrying member for carrying a developer and developing an electrostatic latent image formed on the image bearing member, and a supplying member for contacting to the developer carrying member to supply the developer to the developer carrying member; and a control device for controlling Vdr and Vrs such that Vrs relative to Vdr increases in a direction of a polarity which is the same as a polarity of the developer with the decrease of an absolute value S, where S is a difference between a peripheral speed Sopc of a surface of the image bearing member and a peripheral speed Sdr of the surface of the developer carrying member, Vrs is a voltage applied to the supplying member, and Vdr is a voltage applied to the developer carrying member.