In general, the power transistor and IGBT are used in the switching power supplies for Xenon Arc Lamp as power switching devices. Today it is demanded to simplify the switching power supplies. As the switching frequency becomes higher, simplification of the switching power supply can be attained. But the power transistor and IGBT cannot be used for high-frequency power switching applications. Therefore we propose to use the power MOSFET and its parallel operation. This paper presents considerations on circuit composition of power supply for xenon arc lamp.