Abstract: As a third-generation wide-bandgap semiconductor material, single-crystal aluminum nitride has found extensive applications in power electronics and photosensitive sensing due to its outstanding physicochemical properties. However, due to its inherent brittle and hard properties, nano-grinding processes often encounter issues such as low material removal rates and severe mechanical damage. To investigate the material removal mechanisms of single-crystal aluminum nitride at different grinding speeds, molecular dynamics simulations of diamond grinding on single-crystal aluminum nitride at varying speeds are conducted. The aim was to analyze, at the atomic level, the influence of grinding speed on the nano-/sub-nanometer-scale material removal process. Simulation results indicate that as the grinding speed increases from 50 m/s to 300 m/s, the overall thickness of the subsurface damage layer in single-crystal aluminum nitride decreases significantly, and the residual stress on the surface after grinding also decreases accordingly. Additionally, during the grinding process, dislocations and their derived stacking faults emerge as the primary manifestations of subsurface damage. Increasing the grinding speed effectively suppresses the growth rate of these defects, thereby ensuring the integrity of the subsurface structure post-grinding. These findings provide theoretical guidance for achieving low-damage ultra-precision grinding of aluminum nitride workpieces.