The invention relates to a laser beam welding head for welding metal parts, comprising at least one beam path for a welding beam and means for optically detecting the position of the weld at a first measuring position, wherein the means for optically detecting the position of the weld permit an arrangement of the first measuring position in advance of the welding position of the welding beam in the welding direction and produce a correction signal for correcting the welding position of the welding beam at least as a function of a lateral deviation of the weld from a desired position, and to a corresponding use of the laser beam welding head. In addition, the present invention relates to a method for the beam welding of metal parts, in which the position of the weld is determined at a first measuring position in advance of the welding position of the welding beam using optical detecting means and a correction signal is produced as a function of the deviation of the position of the weld from a desired position. The problem of providing a laser beam welding head and a method for the beam welding of metal parts, with which a very high positioning accuracy and at the same time high welding speeds can be realized, is solved by the distance of the first measuring position (9) in advance of the welding position (8) of the welding beam (2) being selected in such a way that the correction signal produced can be used directly, in particular without preliminary calculation, for activating means (7) for correcting the welding position (8) of the welding beam (2).