Abstract: AA2024-H18 aluminum alloy sheet was hot formed at 435-505℃ with synchronous cooling, and then aged at 150-230℃ for 4-12 h. The microstructure and mechanical properties after aging were studied. The results show that the main strengthening phase in the test alloy after hot forming with synchronous cooling and aging was Al₂CuMg. The size and quantity of Al₂CuMg phase increased with the aging temperature, however, the aging time had little effect on Al₂CuMg phase. The tensile strength and yield strength of the test alloy increased with the increase of the forming temperature, and increased first and then decreased with the increase of the aging temperature. When the forming temperature was not higher than 475℃, the tensile strength and yield strength of the test alloy increased first and then decreased, and reached peak values when aging for 8 h. When the forming temperature was higher than 475℃, the aging time had little influence on the strength of the alloy.