A developing device includes: an image bearing member; a plurality of developing rollers each supplying toner to the image bearing member, and developing an electrostatic latent image on the image bearing member into a toner image; and a hardware processor analyzing values representing density fluctuations during the toner being supplied from the developing rollers to the image bearing member, for the respective developing rollers, and correcting a control value for an image density of at least one developing roller among the developing rollers based on an result of the analyzing so as to eliminate the density fluctuations, in consideration of an effect caused at the developing roller on a downstream side in a rotational direction of the image bearing member by correcting the control value for the image density of the developing roller on an upstream side.