Abstract: Focusing on the pollution and insulation failure of ceramic insulator ring in the ion beam thinner, quartz glass was used as the insulator instead of ceramic material. The quartz glass insulator for ion gun was designed and used. The results showed that the insulator of ion gun based on quartz glass can keep clean and has a high anti-metal dust pollution ability, and can prolong the service life of the instrument. Furthermore, it is economic and durable, which is of important application value.