A laser bonding apparatus, a method of bonding a plurality of semiconductor devices arranged on a main substrate of a workpiece, to the main substrate, and a method of manufacturing a semiconductor package, the laser bonding apparatus including a chamber having a transmissive window and in which a workpiece is accommodatable; a gas supply conduit connected to the chamber and configured to supply a gas at an elevated pressure relative to a pressure outside of the chamber; and a laser generator arranged outside the chamber and configured to irradiate the workpiece accommodated in the chamber, through the transmissive window.