Under extreme high-pressure conditions， the state， crystal phase， and microstructure of explosives may undergo transformations upon impact， thereby affecting the stability and safety of weapon systems. This work focuses on the structural evolution and stability of primary explosives under extreme high pressure， with α-lead azide as the research object. Static high-pressure structural evolution was investigated by diamond anvil cell technique， in situ high-pressure synchrotron X-ray diffraction， and in situ high-pressure Raman scattering spectroscopy. The experimental results show that within the pressure range from ambient pressure to 26.6 GPa， no new diffraction or Raman peaks emerge， confirming that α-lead azide undergoes no structural phase transition. With increasing pressure， however， the spectral peaks gradually broaden and eventually disappear， indicating pressure-induced amorphization of α-lead azide. Further analysis demonstrates that α-lead azide exhibits anisotropic compression. The a- and b-axes show similar and relatively small compressibility， whereas the compression rate along the c-axis is significantly higher. The enhanced dense packing under high pressure is mainly attributed to compression along the c-axis. After full pressure quenching， the spectra do not recover to the initial state， indicating that the pressure-induced amorphization is irreversible. Such irreversible amorphization is attributed to the deformation of azide anions.