PURPOSE: To obtain a reflow soldering device wherein excellent economy and good operational environment are acquired by enabling uniform heating of a wiring substrate without enlarging a heating furnace.

CONSTITUTION: The title device is provided with a carrier conveyor 2 for carrying a wiring substrate 1, a heater 4 which is provided along the carrier conveyor 2 and heats the wiring substrate 1, a plurality of plate-like members 28 between the carrier conveyor 2 and the heater 4, a blower 26 wherein a plate surface 28a of the plate-like member 28 is arranged in a direction to intersect a plate surface of the wiring substrate 1 and a plurality of the plate-like members 28 are provided to slide almost parallel to a plate surface of the wiring substrate 1 and a driving means 29 which oscillates the blower 26.