Abstract: The measurement on the static breakdown voltages for two kinds of pseudospark switches with different electrode structures is presented. A newly designed pseudospark switch with two electrodes of 1 mm-wide annular slots was tested. Comparing the experimental results with that of a typical structure with eight equally-spaced 2 mm-diameter boreholes, it is found that the static breakdown voltage of the former is obvious higher than that of the latter under the same experimental conditions. A maximum hold-off voltage of 41 kV has been demonstrated for the annular-slot structure. Furthermore, the stability of the annular-slot structure is much better than the multihole one evidently.