<p>The growing demand for lightweight and high-reliability components in aerospace and other advanced industries has made machining accuracy and efficiency increasingly critical, yet conventional milling processes still suffer from high cutting forces, rapid tool wear, and surface defects. To address these limitations, this paper proposes an in-situ laser assisted ramp milling (In-LARM) process as a general hybrid machining approach. Using 061 aerospace aluminum alloy as the workpiece material, the applicability of the process and the underlying machining mechanism are systematically explored. By comparing end milling (EM), ramp milling (RM) and In-LARM, it is found that RM reduces the three cutting-force components by 11.8–24.1% compared with EM through progressive axial-radial synergistic feed. With the introduction of a suitable power laser, thermal softening effect further reduces the cutting force by 22.7%-31.5%, while tool wear is reduced, surface abrasion and burr formation are effectively suppressed, and the surface integrity, particularly the bottom surface, is significantly improved. Microstructural analysis shows that the β-Mg₂Si precipitated phase dissolves to form a supersaturated solid solution under appropriate laser power assisted heating conditions, the dislocation density decreases, the thickness of the deformed layer shrinks by 19.8%, and the residual stress decreases due to the thermal mechanical coupling. However, excessive laser heat input induces dislocation entanglement, cutting force rebound, and surface scratch aggravation. The study revealed the competitive mechanism between material softening and tool wear, confirming that optimized laser power can achieve the best synergy between thermal softening and mechanical removal. The proposed process provides a new method for efficient and precision machining of complex structural components, which has positive engineering value for lightweight manufacturing in aerospace.</p>