A magnetic disk apparatus includes a rotation mechanism for driving a magnetic disk, a magnetic head slider being floated in close proximity to a surface of the magnetic disk, a recording/reproduction element for performing recording and playback of information, a drive unit for causing a distance between the record/reproduction element and the magnetic disk to change, and an arrangement to effect position determination of the magnetic head slider, wherein the apparatus has a detection unit for permitting the drive unit to gradually reduce the distance between the record/reproduction element and the magnetic disk and for detecting occurrence of contact therebetween, and a control unit for controlling the drive unit in such a way as to cause, the record/reproduction element to shift in position by a fixed amount to thereby let the distance between this element and magnetic disk increase accordingly.