Two-dimensional finite element (FE) models of SiCp/Al composites were constructed through ABAQUS software, and the influences of the volume fraction, particle size as well as matrix grain size on the mechanical properties were analyzed. Here, the volume fractions of SiC particles in the composites were 15%, 17%, 20%, 25% and 30%, respectively. The particle sizes of 4 μm, 7 μm, 10 μm, 13 μm and 16 μm were selected, and the matrix grain size ranges from 5 to 10 μm. By FE simulation, the elasticity modulus, yield strength, fracture energy and elongation of different microstructures were obtained. The results show that with increasing the volume fraction of SiC particles, the elasticity modulus and yield strength increase gradually, while the fracture energy and elongation decrease. In addition, with the increase in particle size of SiC, all the mechanical properties decrease. Moreover, with the increase in matrix grain size, the mechanical properties of SiCp/Al composites also decrease slightly. The calculation results were in good agreement with the experimental data existing in the literature. The findings obtained in this study could provide a good theoretical basis for designing high-performance SiCp/Al composites.