<p>The effects of different contents of Sc and Zr on the microstructure, mechanical properties and corrosion resistance of 7075 aluminum alloy after T6 heat treatment were studied. After solid solution and two-step aging, coherent Al₃(Sc, Zr) particles effectively pinned dislocations and subgrain boundaries, which hindered the recrystallization process of the alloy and refined the grains. Through fine grains strengthening and Orowan strengthening, compared with 7075 aluminum alloy without adding Sc and Zr, 0.1Sc – 0.2Zr – 7075 and 0.2Sc – 0.4Zr – 7075 aluminum alloys exhibited significant improvement in ultimate tensile strength (increased by 88 MPa and 124 MPa respectively) and yield strength (increased by 138 MPa and 141 MPa respectively). In terms of corrosion resistance, the co-addition of Sc and Zr elements hindered the growth and coarsening of η′ phase, and prevented the formation of larger η (MgZn₂) phase along the grain boundary, reducing the generation of pitting pits, thus improving its corrosion resistance.</p>