A head stack assembly (HSA) protecting member to be installed in the HSA to protect the HSA, and a method of installing the HSA in a hard disk drive (HDD) by using the HSA protecting member are provided. The HSA protecting member includes a first spacer which is interposed between front ends of a pair of suspensions on which a pair of sliders facing each other are mounted, respectively, and which projects to prevent both front ends of the suspensions from contacting each other; a pair of limiters formed above and below the first spacer, such that the front ends of the pair of suspensions can be inserted into the suspension receiving portions, respectively, to restrain the front ends of the suspensions from shaking up and down; and an installation pin formed opposite the first spacer and the limiters and inserted into the HSA.