According to one embodiment, a disk storage apparatus includes a first storage device, a second storage device, and a controller. The first storage device stores data for use in determining influence imposed on tracks peripheral to a designated track in which data should be written on a disk. The second storage device has a nonvolatile cache area for temporarily storing data. The controller performs a cache process of storing the data in the nonvolatile cache area if the influence is determined, from the data, to exceed a reference value, in preparation for writing the data in the designated track.