Abstract: Complex thin-walled structural components undergo clamping deformation during fixture mounting due to their low rigidity. Residual stresses from machining, coupled with mechanical-thermal loading, induce macroscopic structural deformation through stress rebalancing once clamping constraints are released, resulting in dimensional deviations and degraded product quality. To address this, a composite machining strategy combining liquid nitrogen cooling with ice clamping to simultaneously minimize clamping deformation and residual stress release deformation was proposed. A sinusoidal decay function was employed to parameterize the distribution of milling residual stresses. An analytical solution for bending deformation during milling of titanium alloy thin plates was derived based on elasticity theory. A numerical model coupling water phase-change heat transfer with mechanics was developed using the enthalpy-porosity method, to obtain the low-stress distribution state of thin-walled components during ice-fixture clamping. To analyze stress distribution patterns in cryogenic machining, a three-dimensional cutting finite element model for cryogenic milling of thin plates was established, incorporating material's low-temperature constitutive behavior and tool-workpiece contact relationships. Milling experiments on titanium alloy sheets were conducted to analyze cutting forces and heat generation during machining. Results indicate that ice-clamping reduced workpiece deformation by 52.6% and clamping stress by 36.4% compared to conventional clamping methods, achieving near-zero clamping stress in the machining zone. Low-temperature milling experiments under liquid nitrogen cooling conditions achieved feed rates 46.82% higher and peak normal cutting forces 56.98% greater than conventional machining, while reducing milling temperatures by 50.8%. Post-machining surface stress states transitioned from tensile to compressive stress, with a deeper influence layer. Compared to dry cutting, machining deformation decreased by 23.2%.