The objective of this study is to investigate the influence of adding tiny amount of mixed rare earth(La,Ce) and Sr to Al-20Cu-5 Si-2Ni filler metal,by analyzing the microstructure,wettability and mechanical properties of brazed joints.The results show tha with the addition of mixed rare earth(La,Ce) into Al-20Cu-5Si-2Ni alloy,the α-Al solid solution as well as CuAl_2(Ni) intermetallic compound phase significantly reduced,while more Al-Si eutectic phase and Al-Si-Cu ternary eutectic phase were produced.And as mixed rare earth(La,Ce) added in,the wettability of Al-20Cu-5Si-2Ni filler metal decreased,while the shear strength of the brazed joints increased.The addition of Minor Sr modificated Al-20Cu-5Si-2Ni filler metal,further reduced the CuAl_2(Ni) intermetallic compound phase,which was partially replaced Al-Si-Cu ternary eutectic phase.As a result,the tensile strength as well as the wettability of the filler metal was improved. The objective of this study is to investigate the influence of adding tiny amount of mixed rare earth (La, Ce) and Sr to Al-20Cu-5 Si-2Ni filler metal, by analyzing the microstructure, wettability and mechanical properties of brazed joints. The results show tha with the addition of rare earth (La, Ce) into Al-20Cu-5Si-2Ni alloy, the α-Al solid solution as well as CuAl_2 (Ni) intermetallic compound phase significantly reduced, while more Al-Si eutectic phase and Al-Si-Cu ternary eutectic phase were produced. And as mixed rare earth (La, Ce) added in, the wettability of Al-20Cu-5Si- 2Ni filler metal decreased, while the shear strength of the brazed door increased The addition of Minor Sr modificated Al-20Cu-5Si-2Ni filler metal, further reduced the CuAl_2 (Ni) intermetallic compound phase, which was partially replaced Al-Si-Cu ternary eutectic phase. As a result, the tensile strength as well as the wettability of the filler metal was improved.