A paper type detection apparatus includes a surface-property detection unit, a thickness detection unit, and a paper-type setting unit. The surface-property detection unit detects a surface property of paper by performing image processing on image data of the paper read by an image reading unit. The thickness detection unit causes the image reading unit to read the image data of the paper over which a reference chart with a predetermined black density is laid. The thickness detection unit detects the thickness of the paper based on the difference between the black density of the reference chart and the black density appearing on the image data through the paper. The paper-type setting unit sets the type of the paper associated with the detected surface property and thickness of the paper.