In this paper, self-designed Al8Si0.4Mg0.4Fe aluminium alloy was modified with Sr, and a solid solution + aging treatment was applied to the alloy to regulate its microstructure and properties. The results show that: after the modification treatment, the room temperature tensile strength of the alloy did not change much, the elongation at break slightly improved (1.82%→3.34%), and the electrical conductivity significantly increased from 40.1%IACS before the modification treatment to 42.0%IACS. After the modification, the alloy underwent a solid solution treatment at 515°C for 8 hours and subsequently an aging treatment at temperatures 180℃, 200℃, 220℃ and 240℃ for a duration of 6 hours. With the increase of aging temperature, the electrical conductivity increased monotonously from 41.4% IACS to 45.5% IACS, but the room temperature tensile strength increased first and then decreased. At 200℃, the electrical conductivity and room temperature tensile strength of the alloy showed a good coordination, the electrical conductivity was 42.5%IACS, and the room temperature tensile strength was 282.9MPa. When the aging temperature continues to rise, the alloy is overaged. Although the conductivity is still rising, the tensile strength at room temperature decreases sharply, and it is only 177.1MPa at 240℃.