Abstract：A novel gradient aging method and device were developed. The gradient aging treatments with different process parameters were performed on 7075 aluminum alloy bars to investigate their axial temperature, ultimate strength and elongation. The gradient aging temperature field was obtained and contours of aging temperature and ultimate strength were established by FLUENT software. A linear one-dimensional temperature distribution was obtained during gradient aging. The results show that when the axial aging temperature of 7075 aluminum alloy rangs from 66 ℃ to 121 ℃, the ultimate strength increases gradually from 517 MPa to 599 MPa, while the elongation decreases gradually from 12% to 8%. The distribution inaccuracy between experimental aging temperature and that simulated by FLUENT software is less than 2%. The inaccuracy between experimental results and contours of aging temperature and ultimate strength is little. Temperature field during gradient aging process can be controlled and optimized by contours of aging temperature and ultimate strength.