An image forming apparatus comprising: an image supporting member configured to rotate on a rotation axis extending in a predetermined direction; an electrostatic latent image forming section (5, 6) configured to form an electrostatic latent image on the image supporting member; a developing device including a body, a developing roller facing the image supporting member, and a supply member facing the developing roller, the body containing toner, a polish serving to polish the image supporting member and an antifriction serving to lower a coefficient of friction of the image supporting member; a cleaner; and a controller, characterized in that: in the body of the developing device, a supply part where the toner, the polish and the antifriction are supplied to the supply member is provided; the supply member is configured to supply the toner, the polish and the antifriction the supply member received at the supply part to the developing roller while conveying the toner, the polish and the antifriction in the predetermined direction; the developing roller is configured to develop the electrostatic latent image by supplying the toner, the polish and the antifriction received from the supply member to the image supporting member; the controller is configured to drive the electrostatic latent image forming section (5, 6) and the developing device to form a toner patch on the image supporting member, in a facing area capable of facing the developing roller, such that an amount of toner adhering to the image supporting member decreases with increasing distance in the predetermined direction from a predetermined point closest to the supply part with respect to the predetermined direction; and the cleaner is configured to remove the toner patch from the image supporting member. an image supporting member configured to rotate on a rotation axis extending in a predetermined direction; an electrostatic latent image forming section (5, 6) configured to form an electrostatic latent image on the image supporting member; a developing device including a body, a developing roller facing the image supporting member, and a supply member facing the developing roller, the body containing toner, a polish serving to polish the image supporting member and an antifriction serving to lower a coefficient of friction of the image supporting member; a cleaner; and a controller, characterized in that: in the body of the developing device, a supply part where the toner, the polish and the antifriction are supplied to the supply member is provided; the supply member is configured to supply the toner, the polish and the antifriction the supply member received at the supply part to the developing roller while conveying the toner, the polish and the antifriction in the predetermined direction; the developing roller is configured to develop the electrostatic latent image by supplying the toner, the polish and the antifriction received from the supply member to the image supporting member; the controller is configured to drive the electrostatic latent image forming section (5, 6) and the developing device to form a toner patch on the image supporting member, in a facing area capable of facing the developing roller, such that an amount of toner adhering to the image supporting member decreases with increasing distance in the predetermined direction from a predetermined point closest to the supply part with respect to the predetermined direction; and the cleaner is configured to remove the toner patch from the image supporting member. in the body of the developing device, a supply part where the toner, the polish and the antifriction are supplied to the supply member is provided; the supply member is configured to supply the toner, the polish and the antifriction the supply member received at the supply part to the developing roller while conveying the toner, the polish and the antifriction in the predetermined direction; the developing roller is configured to develop the electrostatic latent image by supplying the toner, the polish and the antifriction received from the supply member to the image supporting member; the controller is configured to drive the electrostatic latent image forming section (5, 6) and the developing device to form a toner patch on the image supporting member, in a facing area capable of facing the developing roller, such that an amount of toner adhering to the image supporting member decreases with increasing distance in the predetermined direction from a predetermined point closest to the supply part with respect to the predetermined direction; and the cleaner is configured to remove the toner patch from the image supporting member.