A laser lap welding method for parts made of galvanized steel sheet includes steps of: press-forming two parts from galvanized steel sheet such that the two parts include elongated joining regions to be welded together on mutually opposed surfaces thereof and a plurality of protrusions are formed on at least any one of the joining regions of the two parts at predetermined intervals in a longitudinal direction of the joining region; retaining the two parts in a state in which the joining regions are overlapped one on the other such that a gap according to a height of the protrusions is formed between the joining regions; and irradiating a laser onto one surface of the overlapped joining regions of the two parts such that the overlapped joining regions are fused and welded by energy of the laser, and zinc gas produced with fusing is discharged through the gap.