The solar photovoltaic array fed BLDC motor driven water pump using CUK converter has been proposed to drive the water pumping system. Nowadays solar energy is the best renewable energy resources when compared to the conventional energy resources. The operation of the solar powered pumps is cheaper to run, lower maintenance cost and lower operation. This project deals with the operation of the CUK (DC-DC) converter in solar PV array fed water pumping system as an intermediate DC-DC converter between the solar PV array and soft starting of BLDC motor. Among the several types of converters, a CUK converter is selected and it is used to extract the maximum power which is available from the SPV array and BLDC motor. The intermediate CUK converter with semiconductor switches has the features of reducing ripple current in its output and provide endless region for maximum power tracking (MPPT). The positive output CUK converter performs the changes from positive input source to positiveoutput load source and to avoid the high frequency switching losses BLDC with voltage source inverter can be operated at elementary frequency which results in higher efficiency.