When an optical disk image forming device forms an image on an optical disk, the image forming device reads information of kinds of coloring matters used in an image forming area from information described in an information area of the optical disk. Then, the optical disk image forming device reads from a table laser power strength information corresponding to the information of the kinds of the coloring matters and a maximum linear velocity (Nx) at the time of forming the image and applies a laser beam having this laser power strength to form the image on the image forming area of the optical disk. Thus, since the discoloration of the coloring matter in the image forming area is always saturated, the image having a constant contrast can be formed on the image forming area of the optical disk.