Generally, capacitive energy storage pulsed-power generators, for example a Blumlein generator, and magnetic compression and capacitive-transfer type of circuits, are used as a power supply of a pulse laser exited by discharge. Their operations are possible by using only a closing switch. Many practical and commercial switches have been already developed. An inductive energy storage pulsed-power generator with storage inductor and opening switch can probably realize a lightweight, compact and high-power laser system. But the technology for opening high current is now very difficult, so that the opening switch is being developed and there is a few applications using the generator. The purpose of our research is extension of the application field of this generator by the achievement of application for the laser system, which market is now growing rapidly. Plasma opening switch (POS) is chosen because it is reported that the highest current can flow through it in many switches and it is possible to open the circuit. Although, the theory of POS is not fully investigated and a number of theoretical reports were already published, there is still lack of information about practical applications of the generator with POS. At first, in the experiments, a suitable discharge load was made and the practicable supply voltage and the discharge condition were examined. As a result, when the charge voltage on the main capacitance was 15 kV, the maximum supply voltage was 26 kV and the load current was 8 kA. The discharge condition was transferred from diffuse glow discharge to arc discharge. One of the reasons of these phenomena was the narrow discharge cavity.