Abstract: In order to investigate the characteristics of pulsed CO₂ laser triggering discharge, a high voltage capacitance discharge experimental platform was set up by a pair of hemisphere graphite electrode with 10mm radius and 8mm gap. The real-time data of discharge voltage and current were obtained. Discharge voltage and discharge current were fitted by two-order oscillation circuit model. The impedance of laser induced discharge plasma was obtained. And the discharge time, discharge delay and jitter data were collected. The results show that the impedance of laser trigger discharge plasma is very little, and of 1Ω~2Ω. The fitted plasma impedance slightly decreases with the increase of laser energy, discharge voltage and capacitance. The delay varies from 2μs to 10μs with the change of experimental condition. Delay and delay jitter decrease with the increase of laser energy and discharge voltage. Discharge capacitance has no obvious effects on delay and delay jitter. Laser pulse and high voltage with high stability are helpful for the stability of laser triggered discharges.