The additive manufacturing of Al-Mg-Er-Zr high-strength aluminum alloy is achieved by selective laser melting （SLM） technology to meet the demand for structural components.The formation quality of the alloy is optimized by controlling the laser power and scanning speed，and the influence of heat treatment temperature on the mechanical properties of the aluminum alloy is investigated.The results show that the suitable laser power and scanning speed can control the pores and defects，and the density of samples is also improved.The optimal process parameter is as follows：laser power 280 W，scanning speed 1.2 m/s， scanning pitch 0.08 mm，and layer thickness 0.03 mm. In addition，the tensile strength and yield strength of aluminum alloy increase as the heat treatment temperature increases，while the elongation decreases.The maximum tensile strength of the sample exceeds 500 MPa when the heat treatment temperature is 350 ℃ and the holding time is 2 h，and the elongation is greater than 10%.Finally，the high-strength aluminum alloy samples with good appearance and qualified internal quality are obtained，which laies the technical foundation for the application of high-strength aluminum alloys by SLM in aerospace.