Abstract: In the experiment, a laser filler wire welding method was used to weld the welding seam of a car seat, and the effect of laser power, wire feeding speed and defocusing amount on the stability of the laser filler wire welding process was studied by using high-speed cameras.The experimental results show that reducing the laser power or increasing the wire feeding speed can reduce the porosity; when the defocus amount is 0, the porosity is the lowest.The welding stability depends on the droplet transfer mode.When the droplet transfer mode is liquid bridge transfer, the stability of laser wire-filled welding is improved.