With the aim of studying the characteristics of laser-triggered surface flashover in pulsed voltage, synchronization problem of laser pulse and voltage pulse is solved through a high precision trigger system. The experimental platform of laser-triggered surface flashover in pulsed voltage is built up in the laboratory. A single/double harmonic, with wavelength λ of 1064/532 nm, Q-switched Nd:YAG laser is applied to trigger the surface flashover. Based on the platform, experiment of laser-triggered surface flashover is carried out using the flat electrodes and columned insulators. The material of electrode is stainless steel and the electrode diameter is 100mm. Three kinds of insulations are tested in the experiment. The materials of insulations are nylon, polycarbonate and Al 2 O 3 , respectively. The diameter of insulation is 20mm, and insulations' thickness are 6mm, 8mm and 10mm. Laser pulse's wavelength are 532nm and 1064nm, and laser is focused with 2mm×30mm rectangle. The results of experiment show that flashover delay time and jitter time decrease with increase of pulsed voltage and laser energy density. In addition, the comparison of the three kinds of insulation is obtained through the result.