A head suspension assembly of a disk device comprises a head having a femto-slider, which is flied by an air current generated between the slider and a surface of the recording medium as the recording medium rotates, and a recording element which is provided on the slider and performs information processing for the recording medium, and a suspension which supports the head with respect to the recording medium and applies a head load bound for the surface of the recording medium to the head. The suspension has a thickness of less than 50 .mu.m and the head load of 2.0 gf or more.