Abstract The present work aims to investigate the relationship between the mechanical behavior and composite structure of silicon carbide (SiC) particle reinforced aluminum matrix composites. On account of newly developed particle size analysis technique, a large number of SiC particles are experimentally measured to provide statistical particular structural information. According to the statistical analysis and physical observations of SiC particles, the composite structures of SiC/Al composites are numerically reproduced in line with their actual microscopic structures, in which a developed structural modeling program can build the randomly dispersions of the particle sizes, the particle shapes, the particle positions and the volume fractions of SiC particles. Elastoplastic material properties, strengthened matrix properties and particle–matrix interfacial behaviors are introduced to simulate the mechanical behavior of SiC/Al composites. Enough fine meshes and reasonable loads and boundaries conditions can efficiently guarantee the computing accuracy and reduce the computing cost. A lot of simulating results of SiC/Al composites are provided and verified with the related experimental results. This work makes an effective attempt to establish the relationship between the actual composite structures and the mechanical behaviors within the particle reinforced metal matrix composites.