This paper proposes a method for the modelling, simulation and analysis of solar PV water pumping system. A submersible type variable speed DC water pump system is considered in this study under different pumping heads (50 m, 60 m and 70 m) and for 8S x 3P PV array configuration. The hourly electrical performance of the PV array was estimated from the maximum power points of the I-V curves, as the maximum power point tracking (MPPT) controller continuously optimizes the output power of the PV array. The performance equation which relates the flow rate of the pump with pump head and power input to the pump is modelled from the manufacturer's performance curve with curve fitting technique. Using the generated equation and the calculated hourly power output data, the hourly performance of the solar driven water pump system was estimated for of different pump head. The analysis and simulation results show that a lower pump head results in higher flow rate regardless of the variation in solar irradiation level. The obtained result also indicated that an increase in solar radiation intensity resulted in an increasing of the pump flow rate, pump efficiency and system performance.