Abstract: The effects of solution time, aging temperature and aging time on the microstructures and mechanical properties of 6061 aluminum alloy formwork for green building were studied by metallographic microscope, transmission electron microscope and tensile testing machine. The results show that, with the increase of solution time, aging temperature or aging time, the tensile strength, yield strength and hardness of 6061 aluminum alloy first increase and then decrease, while the elongation after fracture decreases first and then increases. When solid solution at 535 ℃/60 min and aging at 180 ℃/7 h,the maximum values of the tensile strength, yield strength and hardness are 314.7 MPa, 304.3 MPa and 145.52 HV,respectively, and the elongation is 10.8%. The main strengthening mechanisms of 6061 aluminum alloy are fine grain strengthening, solution strengthening and second phase strengthening.