Particle reinforced metal matrix composites (MMCs) have the very large potential to provide ultrahigh mechanical properties,for example specific stiffness and specific strength, in the civil and defense applications as well as the automotive andaerospace industries . Considering the materials characteristics and producing processes, composite structures of particlereinforced MMCs largely depend on their reinforced particles , such as: the sizes, the shapes, the positions and the contents inthe MMCs. Meanwhile, the particle-matrix interfaces are also largely retained and they further affect the mechanical behaviorsof particle reinforced MMCs . However, it is very difficult to completely use experimental analysis to find the key parametersin the composite structures, which should be improved to optimize the overall tensile behavior of particle reinforced MMCs. Along with structural modeling of particle reinforced MMCs, the cohesive interfacial model was introduced to carry outthe mechanical deformation of particle reinforced MMCs . These structural models of particle reinforced MMCs are basedupon experimental observations that can provide useful guidelines to a certain extent for optimum composite structures design.Therefore, a long way still exists to go before the potential of particle reinforced MMCs can be wholly achieved to develop newstrong and lightweight materials in both material design and industrial applications.The present work aims to investigate the intrinsic relation between the mechanical behavior and composite structure couplingwith particle-matrix interfacial behavior within the particles (e.g. SiC and CNT) reinforced aluminum matrix composites [6, 7].Based on the statistical geometrical information of numerous reinforced particles, a developed three-dimensional (3D) structuralmodeling program can not only establish structural models close to reality of reinforced particles, but also reproduce compositestructures similar to those of actual particle reinforced MMCs. In these created structural models, the random dispersions of thesizes, the shapes, the positions and the contents of reinforced particles can be realized according to the structural characteristicsof composites. To perform the mechanical behaviors of particle reinforced MMCs, elastoplastic mechanical properties withparticle-matrix interfacial behaviors are applied, and reasonable loads and boundaries are conducted. The results indicate thatthe particle content, matrix strengthening and interfacial behavior play the significant role in the enhancing effect, in order tounderstand the mechanical deformation in the particle reinforced MMCs.