A magnetic disk, comprises, a magnetic disk, a disk driving portion for driving the magnetic disk, a slider, mounting thereon a recording element and a reproducing element, for generating a recording magnetic field, and a heating element for use in generation a near field light, and a driver portion for positioning the slide above a desired track of the magnetic disk, wherein the magnetic disk has a recording layer, an overcoat layer formed on the recording layer, a lubricant provided on the overcoat layer, wherein the overcoat layer has a first overcoat film and a second overcoat film, which is formed on the first overcoat film, or has structure of laminating a plural number of overcoat films, and within an inside thereof are provided a plural number of interfaces between different materials and/or grain boundary surfaces.