Abstract: The optimized experiment of non-penetrating welding of TC4 titanium alloy was carried out by high power scanning galvanometer fiber laser beam welding and the effects of galvanometer scanning parameters on weld formation were analyzed. The weld formation differences between scanning galvanometer laser welding and conventional laser welding were also analyzed. The results show that the circular scanning track is more conducive to obtain well-formed welded joint. When the laser scanning frequency is controlled in the range of 50-150 Hz and the scanning amplitude is controlled in the range of 0.6-0.9 mm, the weld seam is formed uniformly and there is almost no welding spatter. With the increase of laser scanning amplitude, the weld width increases gradually, while the weld penetration decreases gradually. Compared with that of the conventional laser welding, the depth to width ratio of the scanning galvanometer laser welded joint reduces slightly; however,the surface quality and internal quality are improved significantly, which is more conducive to the further improvement of the joint performance.