The research studied the combined effects of ultrasonic vibration (USV) and manganese on the Fe-containing inter-metallic compounds and mechanical properties of Al-17Si-3Fe-2Cu-1Ni (wt.%) alloys. The results showed that, without USV, the alloys with 0.4wt.% Mn or 0.8wt.% Mn both contain a large amount of coarse plate-like δ-Al4(Fe,Mn)Si2 phase and long needle-like β-Al5(Fe,Mn)Si phase. When the Mn content changes from 0.4wt.% to 0.8wt.% in the alloys, the amount and the length of needle-like β-Al5(Fe,Mn)Si phase decrease and the plate-like δ-Al4(Fe,Mn)Si2 phase becomes much coarser. After USV treatment, the Fe-containing compounds in the alloys are refined and exist mainly as δ-Al4(Fe,Mn)Si2 particles with an average grain size of about 20 μm, and only a small amount of β-Al5(Fe,Mn)Si phase remains. With USV treatment, the ultimate tensile strengths (UTS) of the alloys containing 0.4wt.%Mn and 0.8wt.%Mn at room temperature are 253 MPa and 262 MPa, respectively, and the ultimate tensile strengths at 350 °C are 129 MPa and 135 MPa, respectively. It is considered that the modified morphology and uniform distribution of the Fe-containing inter-metallic compounds, which are caused by the USV process, are the main reasons for the increase in the tensile strength of these two alloys. The research showed the combined effects of ultrasonic vibration (USV) and manganese on the Fe-containing inter-metallic compounds and mechanical properties of Al-17Si-3Fe-2Cu-1Ni (wt.%) Alloys. , the alloys with 0.4 wt.% Mn or 0.8 wt.% Mn both contain a large amount of coarse plate-like δ-Al4 (Fe, Mn) Si2 phase and long needle- like β-Al5 (Fe, Mn) . When the Mn content changes from 0.4 wt.% To 0.8 wt.% In the alloys, the amount and the length of needle-like β-Al5 (Fe, Mn) Si phase decrease and the plate- like δ-Al4 After USV treatment, the Fe-containing compounds in the alloys are refined and existed mainly as δ-Al4 (Fe, Mn) Si2 particles with an average grain size of about 20 μm, and only a With USV treatment, the ultimate tensile strengths (UTS) of the alloys containing 0.4 wt.% Mn and 0.8 wt.% Mn at room temperature are 253 MPa and 262 MPa , respectively, and the ultimate tensile strengths at 350 ° C are 129 MPa and 135 MPa, respectively. It is considered that the modified morphology and uniform distribution of the Fe-containing inter-metallic compounds, which are caused by the USV process, are the main reasons for the increase in the tensile strength of these two alloys