The present invention relates to a reel-to-reel layer reflow method, which emits a uniformized laser beam, which can easily adjust the emission area, and which is for the purpose of improving productivity. An embodiment of the present invention provides a reel-to-reel layer reflow method comprising the steps of: a) transferring a substrate, which has been wound in a roll type, to one side while unwinding the same; b) forming a solder portion on the substrate; c) seating an emission target element on the solder portion and seating a non-emission target element on the substrate; d) surface-emitting a laser beam to the solder portion, on which the emission target element is seated, such that the emission target element is attached to the substrate; e) inspecting the substrate structure manufactured through said step d); and f) winding the substrate structure in a roll type.