Abstract In the current study, three-dimensional theoretical model of the photovoltaic (PV) panel coupled with a heat spreader is carried out. A thermal model is constructed and solved mathematically by using ANSYS software. The effect of coupling the heat spreader with the PV and the heat spreader dimensions on the PV cooling and performance is studied. Also, the effect of solar radiation intensity and weather conditions (wind speed and ambient temperature) on the performance of PV with heat spreader system is considered. The model is validated with the previous results found in the literature. Moreover, the temperature distribution of the PV with the heat spreader is presented. The results show that the optimum thickness and cross sectional area of the heat spreader for PV dimensions of 125 × 125 mm are 10 mm and 0.3 m2. The cell temperature is decreased by 15 °C when the heat spreader is used with the PV. Also the average power output and efficiency of the PV module are increased by 9% when the heat spreader is used.