The invention provides a method of laser welding. The method of laser welding includes high-speed movement of a linear motor platform, in the first segment of welding waveform, the power of a laser device is zero in the first time, a linear motor drives a welding head to perform the first round trajectory movement in the preset welding trajectory, and that is to say, the laser device does not emitlight from the starting welding segment to a first welding ending point; in the second segment of welding waveform, the power of the laser device rises to 100% in the second time, the motor drives the welding head to perform the second segment of round trajectory welding on a battery sealing nail; and in the third segment of welding waveform, the power straight line of the laser device in the third time is gradually changed to zero, the laser device performs straight beads in the third time so as to perform arc retreating, and the straight beads start from the first welding ending point to asecond welding ending point. The method is used for preventing the broken welding and cold joint phenomena during high-speed welding of the sealing nail, the length of a weld joint overlapping segmentis controlled by means of wavy arrangement, the distance of the overlapping segment is reduced, the possibility of broken welding and cold joint is greatly reduced, and the broken welding and cold joint phenomena can be effectively avoided.