A laser welding method includes a step of placing a third material between a first material and a second material. The first material and the second material are of metals so as to be weldable to each other, and at least one of which has a protrusion part. The third material is difficult to weld to the first material and the second material and has a through-hole part into which the protrusion part is inserted. The method also includes a step of emitting laser light from the first material side toward a region corresponding to the protrusion part under condition in which the third material is sandwiched between the first material and the second material, so that the first material and the second material are welded via the through-hole part. In the step in which the third material is sandwiched between the first material and the second material, a first gap is disposed between the protrusion part and the inner peripheral face of the through-hole part, and a second gap depending on the plate thickness of the first material in the region corresponding to the protrusion part is disposed between the first material and the second material in the region corresponding to the protrusion part.