Abstract: Photoconductive semiconductor switches (PCSS) have been used in pulsed power technology due to their advantages over conventional switches, such as fast rise time, negligible time jitter, and optical electrical isolation. History and developments of GaAs PCSS are summarized. SiC with wide band gap, high breakdown field, high saturation electron drift velocity and high thermal conductivity is considered as a promising semiconductor for PCSS. Status and latest progress of SiC PCSS employing intrinsic and extrinsic photoconductivity are reported. Applications of PCSS in ultra-wide band and compact pulsed power system are briefly introduced. The critical technological problems to be investigated in future are presented.