This work presents a field study for the performance of a photovoltaic (PV) module under cooling with pure water or PCM in aluminium channels beneath the PV panel. Two systems each of0.37 m2commercial poly-crystalline PV panels have been installed at the Faculty of Engineering at Shoubra, Benha University, Cairo, Egypt (30.1N Latitude).One of them is cooled using the water or the PCM with different occupation of each in the channels; 100%water (0%PCM) to 0% water (100%PCM), and compared with the uncooled panel during July 2017.The results showed that the PV temperature decreases as the cooling water flow rate increases in the channels. In addition, compared with the uncooled panel, using 100% water in the channels provides an increase in the electrical efficiency of 33.4% and 45.5% when the flow rate increases from 0.25 to 1.0 L/min, respectively, while with using 100% PCM, the increase in the electrical efficiency is 15.5%. The average thermal efficiency increases from 44.2% to 68.4% for 100% water when the cooling water flow rate was varied from 0.25 to 1.0 L/min. Furthermore, the percentage increase in the PV electrical power for the 100% water cooled PV is higher than that of the PCM-cooled PV. The average percentage increase in the PV electrical power for 100% water augments from about 24.1% to 28% at flow rates of 0.25 to 1 L/min, respectively. Finally, the average percentage increase in the PV electrical power is 12.4% for 100% PCM cooling technique.