The present invention provides a reflow apparatus and method which can make the running direction of the internal gas flow in a heating section within a reflow furnace constant. A circulating gas path is formed in a heating unit (U) which collects and moves the gas flow (B) from a sirocco fan (11) up to the rear side of the heating unit (U) and at the same time, drops the raised gas flow towards a circuit board (2) on a transfer path from the front side of the heating unit (U). Moreover, a plurality of straightening plates (16) are arranged above the transfer path of the heating unit (U) so as to guide down the hot gas flow (B) running forward to the circuit board (2) on the transfer path. A blow-down nozzle (17) is further constituted of a plurality of plate materials (19) aligned in rows in the transferring direction of circuit boards and having an inverse U-shaped cross section. The blow-down nozzle (17) is arranged below the straightening plates (16) to feed the hot gas flow (B) to the whole surface of the circuit board (1) in the vertical direction uniformly. <IMAGE>
