The method of bonding flying leads is capable of efficiently supersonic-bonding the flying leads to pads of a board and improving bonding reliability therebetween. The method comprises the steps of: positioning the flying leads to correspond to the pads arranged parallel; and applying supersonic vibrations to a bonding tool so as to respectively bond the flying leads to the pads. And widths of the flying leads are wider than those of the pads, and supersonic vibrations are applied to the bonding tool, which is pressing the flying leads onto the pads, so that the flying leads are respectively supersonic-bonded to the pads.