A method of bonding a metal ball for a magnetic head assembly is provided. The method comprises: preparing a capillary; disposing the capillary so as to face a bonding surface of the electrode pad of the slider and that of the electrode pad of the flexible printed circuit board; carrying the metal ball to the bonding surfaces by introducing the metal ball and the inactive gas stream into the carrying route of the capillary; positioning and retaining the metal ball on the bonding surfaces by the inactive gas stream passing through the carrying route and issued radially from the cutoff portions; and melting the metal ball by directly applying laser beams via the cutoff portions of the capillary, and bonding the electrode pad of the slider and the electrode pad of the flexible printed circuit board by the melted metal.