An image forming apparatus includes a light scanning device, a developing portion, a control portion and a storage portion. The storage portion stores an evaluation chart. The evaluation chart includes a first evaluation pattern and a second evaluation pattern. The first evaluation pattern includes a first patch row. The first patch row is formed by arranging a plurality of first evaluation patches. The first evaluation patch includes a first dot row and a second dot row. The second evaluation pattern includes a second patch row. The second patch row is formed by arranging a plurality of second evaluation patches.