This study focuses on the performance of vertical photoconductive semiconductor switch (PCSS) based on Fe: β-Ga₂O₃ under high voltage. The results show that deep levels in Fe: β-Ga₂O₃ can provide carriers of non-intrinsic excitation. The device did not exhibit breakdown tendencies when subjected to a 20 kV input voltage with single-shot laser triggering. After more than 5000 trigger cycles at 15 kV by a 10 Hz laser, the switch eventually failed. Nevertheless, pulse performance remained stable throughout the effective data collection period, preliminarily demonstrating the potential of Ga₂O₃ PCSS for applications in extreme conditions such as high power and high frequency. Failure analysis indicates that a wide bandgap is not the sole determinant of high breakdown voltage. In addition to employing precise doping techniques to introduce specific defects and modify material properties, further improvements in existing material growth methods and device packaging structures can also contribute to enhancing the output and lifetime of PCSS.