[en] For the need of intense current electron accelerator, a high voltage, long-life gas spark switch was designed. Anti-pollution design is used in the switch, the outer housing of the switch is made of Cu and a metal baffle is used to prevent the top plate from pollution. These measures can prevent arc form approaching the insulated bracket as far as possible and increase the life of the switch. And the electrode structure is optimized with electromagnetic simulation software. The experimental results indicate that the operating voltage is 32-42 kV and charge transfer is about 0.38-0.48 C per pulse at 0.1-0.2 MPa pressure, and the switch works stably and reliably. (authors)