Abstract: RFPA(Realistic Failure Process Analysis) code was used to investigate the matrix-inclusion interfacial debonding process of particulate reinforced composites. In this numerical model, the particulate reinforced composite was assumed to be three-phase, namely, it is composed of matrix, particulate and the interfaces between them. The maximum tensile strain criterion and Mohr-Coulomb criterion were utilized as the damage threshold of the element. The single inclusion and multiple inclusions reinforced composites models were studied respectively. Numerical results of the stress distribution and the interface debonding type agree well with the results obtained from MARC and ABAQUS.