PURPOSE: To provide the flux-contg. Al alloy brazing filler metal with which a sufficient flux effect is obtainable even at a low temp. and good brazing is possible.

CONSTITUTION: The first flux-contg. Al alloy brazing filler metal is a flux-contg. Al alloy brazing filler metal contg. Al, Si and Cu as a brazing filler component and a flux component. The content of Si in the brazing filler component is 0.05 to 20wt.% and the content of Cu therein is 5 to 10wt.%. The flux component is a fluoride flux which contains KF, LiF and CsF and is compounded with these components in a range enclosed by a liquidus line of 550°C in a ternary state diagram of KF-LiF-CsF. The brazing filler component and the flux component are compounded at 99.9:0.1 to 70:30 ratios by weight and the density is ≥90% of the theoretical value. The second flux-contg. Al alloy brazing filler metal is made of the compsn. which is further added with 5 to 20wt.% Zn as the brazing filler component.