Water pumping system has become one of the most feasible photovoltaic (PV) applications. Moreover, PV pumping is getting more attention in recent days mainly in remote areas where connection to the grid is technically not possible. Power generation by Photovoltaic is reliable. The simplest PV water pumping system consists of a PV array connected to boost converter feeding power directly to a DC motor or PMDC motor and a pump. This paper deals with the simulation of PV based DC motor pumping system and PMDC motor pumping system. The comparison of the two systems has been done and proved a simple but efficient photovoltaic water pumping system among them. Motors and centrifugal pumps operate at variable speed in a photovoltaic pumping system. However, the characteristics of motors and pumps are usually only given for a single voltage and speed. To analyze operation of a pumping system, where the solar radiation causing variation in the photovoltaic power, the input/output relationship of the motor-pump assembly and motor characteristics must be determined. The results obtained from the simulation of the system are satisfactory. It is found that PMDC pumping system is better.