Abstract: The effects of aging treatment on the mechanical properties and microstructure of 6061-T6 aluminum alloy plates were investigated by using experimental methods such as tensile tests, scanning electron microscopy and optical microscopy. The results show that, the aging temperature is too low or the aging time is too short, the dispersion strengthening effect of the alloy is weakened, while the aging temperature is too high or too long, the precipitated grain size becomes larger.With the increase of aging temperature, the tensile strength increase first and then decrease, and the maximum tensile strength of the aluminum alloy is 336 MPa at aging temperature of 190 ℃. The maximum elongation after break is 21.47% at aging temperature of 150 ℃ and aging time of 2 h. The hardness of 6061-T6 aluminum alloy is influenced by aging temperature, but less by aging time, and reaches the maximum hardness of 114.2 HV at aging temperature of 170 ℃ and aging time of 2 h. The maximum hardness of 114.2 HV is achieved at an aging temperature of 170 ℃ and an aging time of 2 h. The tensile fracture analysis shows that with the increase of aging temperature and aging time, the number of tough nests becomes less and the depth becomes shallower, and the plasticity of the material is poor.