PURPOSE: To perform simultaneous brazing of several positions with the brazing material infiltrated in holding parts, by providing clearances to the positions of base materials to be brazed to each other by means such as bending, engaging, fitting or the like, holding said positions, disposing the brazing material in the holding parts and heating the assembly in a heating furnace.

CONSTITUTION: The positions of base materials to be brazed to each other are held by tentative holding means, whereby said parts are exactly positioned. The several positions are simultaneously brazed in a heating furnace, whereby the local heating of the base materials A, B is eliminated hence distortion is eliminated. The temp. conditions in the heating furnace can be exactly controlled, whereby the rough surface on the soldered parts is prevented. Since the conditions for the atmosphere gas in the heating furnace are controllable to an oxygen gas-free state, a state contained with a reducing gas, etc., the oxidation in the brazed parts is prevented, prompt plating is permitted and the fine working is made easy.