A density detection apparatus includes the following elements. A storage unit stores therein image information. A measuring unit measures amounts of light components reflected by an image carrier or density detection images represented by the image information. A light amount obtaining unit obtains a variation in amounts of light components reflected by each region in which the associated density detection image is formed, and obtains, as a reference value, a representative value of the amounts of light components. An image correcting unit corrects the image information by changing an arrangement order of the density detection images. An image forming unit forms the density detection images on the image carrier on the basis of the corrected image information. A density obtaining unit obtains density levels of density detection images corresponding to their area ratios by using the amounts of light components reflected by the density detection images and the reference values.