Surface flashover triggered vacuum switch (STVS) working performance mainly depends on the electrical characteristics of trigger pulse. This article presents an experimental investigation of the trigger process. The influence of the electrical properties of the trigger pulse on the trigger characteristics is focused. Based on the self-developed high-performance STVS product, the experimental test platform was established. The experimental results show that a shorter delay time of STVS can be obtained by heightening trigger voltage. However, the effect of trigger voltage on time jitter is not obvious. The slight increase in trigger current has evident influence on trigger delay time. It also does not affect the stability of trigger delay. With the increase in trigger voltage rise rate, the trigger delay time and time jitter can be optimized. Finally, the long-term stability of STVS is discussed. After 300 trigger times, the delay time changes from about 140 ns to more than 150 ns and the jitter changes from about 5 ns to more than 10 ns. In the design of STVS products, it is recommended to adopt a trigger system with a fast rise rate of trigger voltage and trigger current.