Embodiments of the invention make it possible to conduct stable recording on a magnetic disk, even in case of changes in flying height due to thermal protrusion. In one embodiment, a compensatory recording current value A2 is used when a first section of user data is recorded in the required number of data sectors from the data sector of the starting address for recording the user data to the data sector of an intermediate address. A recording current value A3 smaller than the compensatory recording current value is used when a second section of user data is recorded in the data sectors existing from the data sector of the intermediate address towards the ending address.