Large aircraft structural components are highly susceptible to complex deformation under the influence of residual stress fields after machining. An optimization method of machining sequence based on in-situ inference of residual stress fields was proposed. The proposed method monitored workpiece deformation forces in real-time during the rough machining stage, in-situ infered the blank residual stress field distribution, and employed the temporal uniformity of deformation forces as an evaluation criterion, combined with finite element simulation, to achieve machining sequence optimization. Comparative experiments were conducted on a three-meter-scale aluminum alloy aircraft structural component. The experimental results demonstrate that after optimization, 99.31% of the global deformation of the part is less than 0.2 mm, the proportion of the high-precision region (deformation ≤ 0.1 mm) increases from 48.48% to 81.94%, and the average deformation decreases from 0.109 mm to 0.059 mm. This method effectively suppresses the machining deformation of large structural components.