Image forming apparatus and image forming method

An image forming apparatus includes an image processing unit and a switching unit. The image processing unit includes: a charging unit that is provided to face an image carrier and applies a direct current voltage on which an alternating voltage of a first frequency is superimposed to charge the image carrier; an electrostatic latent image forming unit that forms an electrostatic latent image on the charged image carrier with light scanning based on image information; a developing unit that develops the electrostatic latent image; and a transfer unit that transfers the developed image to a recording medium. When an image density based on the image information is greater than or equal to a specific image density, the switching unit switches a frequency of the alternating voltage at least during charging performed by the charging unit to a second frequency different from the first frequency.