In this paper, the performance of a solar photovoltaic water pumping system was improved by maintaining the cell temperature in the range between 30 °C and 40 °C. Experiments have been conducted on a laboratory experimental set-up in-stalled with 6.4 m2 solar panel (by providing air cooling either on the top surface or over the beneath surface of the panel) to operate a centrifugal pump with a rat-ed capacity of 0.5 HP. The performance characteristics of the photovoltaic panel (such as, cell temperature, photovoltaic panel output, and photovoltaic efficiency), pump performance characteristics (such as pump efficiency and discharge), and system performance characteristics are observed with reference to solar irradia-tion, ambient temperature and wind velocity. A thermal model has been developed to predict the variations of photovoltaic cell temperature based on the measured glass and tedlar temperatures. The influences of cell temperature and solar irradi-ation on the performance of the system are described. The results concluded that cooling of photovoltaic panel on beneath surface has maintained the cell tempera-ture in the range between 30 °C and 40 °C and improved the overall efficiency by about 1.8% when compared to the system without panel cooling. © 2017 Society of Thermal Engineers of Serbia.