In the present work, the finite element analysis was employed to study the distribution and level of thermal residual stress generated in matrix reinforced with SO2 nanoparticles. Using Cohesive Element as the bonding of the interface between fiber and matrix, three–dimensional finite element models of periodic cells were established. The results of the models with and without nanoparticles were compared. The residual thermal stressdue to the mismatch of the thermal expansion coefficients between matrix and fibers, especially theshear stress in the interface, decreased with nanoparticles, which could explain the reinforcing mechanism of nanoparticles. Our numerical study can be of great significance in designing new composites with high performance