This research aims to investigate the local aggregation effect on tensile strength of particulate composites with an embedded crack. A micromechanical finite element model (FEM) accounting for the configuration of particle distribution was proposed to study the particle aggregation effect on the fracture behavior of composites. Results reveal that increasing particle size can deteriorate the tensile strength of the composites. The declining behavior would become worse as particle aggregation taking place. Moreover, the decreasing tendency in tensile strength was also observed in the composites with high particle volume fraction in conjunction with high extent of particle aggregation. Therefore, the phenomenon that the particle local aggregation in composites results in the reduction of tensile strength is in a good agreement with experimental observations.