ÖzSolar energy has advantages such as accessibility, applicability, and predictability compared to other renewable energy sources. This energy source is used for many purposes in the world. Photovoltaic panels provide applications such as generating electricity from solar energy or heating and cooling. Their performance changes depending on the PV panel material, the amount of solar radiation, and the operating temperature factors. In the electrical energy conversion of PV systems, overheating of the PV module leads to a decrease in power generation and causes a decrease in efficiency. Therefore, there are cooling methods, divided into two categories as passive and active for cooling of PV panels. In this study, the properties of the phase change material (PCM) used in the cooling of PV panels are given. Furthermore, experimental and numerical studies of PCM in PV cooling and PV/T systems are reviewed in order to improve PV panel efficiency. PCM is reported to reduce the temperature of PV panels and increase the efficiency and power output data obtained.