<p>High-energy solid propellants serve as the principal energy source for artillery systems and rocket propulsion. A comprehensive understanding of their impact-induced damage mechanisms is essential for ensuring the safety, reliability, and overall performance of these explosive systems. Investigating the crack propagation mechanisms within propellants from a mesoscopic perspective is of significant importance for understanding their mechanical properties. Nevertheless, the majority of existing models predominantly concentrate on particle morphology, dimensions, and volumetric fractions, while frequently neglecting the intrinsic micro-voids within the material’s structure. This study examines the mechanical behavior, damage modes, and damage mechanisms of solid propellants with varying void content and shapes under dynamic compressive loading through the cohesive zone model. Crack parameters and the distribution of damaged elements in each mesoscopic component are determined to quantitatively characterize the porosity dependence of the propellant and elucidate the mechanisms of crack propagation and the transition of damage modes at various porosity levels. The findings of this study provide valuable insights into the nonlinearity of the macroscopic mechanical behavior of propellants containing void structures and the influence of strain rate on mesoscopic damage modes. These insights are instrumental in guiding the manufacturing process of propellants and contribute to a more accurate and rigorous investigation of their mechanical properties.</p>