The invention provides active brazing filler metal for a diamond saw blade. Aluminum, silicon and nickel are compounded on the basis of copper, tin and titanium active brazing filler metal, so that diamond products can be sintered or brazed under gas shield, the production process can be beneficially simplified, and the production cost can be reduced. The active brazing filler metal is also rolledand prepared into a sheet shape. The process comprises the following steps of carrying out rough rolling, medium rolling and finish rolling on a cast-rolling or hot-rolled blank with the thickness of0.35 to 0.65 mm in the presence of rolling oil to obtain sheet-shaped brazing filler metal with the thickness of 0.0075 to 0.0099 mm, wherein obtained solder alloy has good wettability to diamond andis low in melting point. Under the solid solution strengthening effect of elements aluminum and nickel and a plurality of effects of active element titanium and the like, when the active solder alloyis used for brazing diamond and base metal, the diamond and the base metal can form firm metallurgical bonding, and the shear strength of a graphite/ #45 steel joint brazed by the active brazing filler metal can reach 355 MPa.