An image density control device includes a first detecting unit that detects a light amount of first specular reflected light which is reflected from a surface of an image carrier, a second detecting unit that detects a light amount of first diffuse reflected light which is reflected from an image on the surface of the image carrier, a surface change information acquiring unit that acquires a surface change information which shows changes with time, and a control unit that corrects the light amount of the first specular reflected light by using the surface change information to a light amount of second specular reflected light, and controls the density of the image by using the light amount of the first diffuse reflected light and the light amount of the second specular reflected light.