The invention discloses a handheld laser welding method and a handheld laser welding device. When the handheld laser welding device is used for welding, a laser beam emitted from a handheld laser welding head which is held by a hand is required to be focused on a relative position of a part to be welded; indicating red light is adopted for spatial positioning in a welding process; the handheld laser welding head outputs the laser beams which are generated by an Nd:YAG laser or a fiber laser and two indicating red light beams which are exclusively and just converged at a central position of a focal plane of the laser beams output for welding; and the two indicating red light beams which can be converged at one point are used for indicating the welding.