Concentration photovoltaic/thermal (CPV/T) system provides, an effective way to increase the efficiency of traditional PV system. The system is producing both electric and thermal energy and recovering thermal energy at high temperature. This paper presents a model and simulation of CPV/T systems. It uses the MATLAB program to build the CPV/T. It includes modeling of the reflective optics with parabolic mirror concentrator and the triple-junction cells (InGaP/InGas/Ge) assembled with a dual axis tracker. Also an active cooling system of the photovoltaic cells is considered. The model adopts a mathematical approach in order to simulate and investigate the cell characterization curves including module electric and thermal efficiencies, thermal and electric energies provided by cell and module, and cooling fluid temperatures. The model works for different time levels (yearly and daily) in terms of direct normal irradiance measured practically and the results were presented.