Local electric field is an important parameter in discharge plasma. Non-intrusive diagnosis of electric field with a high spatial-temporal resolution is of great significance to understand the mechanism of discharge evolution. In this work

existing electric field measurement methods were reviewed and their limitations were discussed. Based on the electric field induced second harmonic（EFISH） generation principle

the non-intrusive measurement of transient electric field was realized by using nanosecond pulsed laser. The measurement system was calibrated using uniform electrostatic field generated by parallel plate electrode structure and a linear relationship between the amplitude of second harmonic signal and the square of electric field was obtained. Afterward

based on the calibration result

the temporal evolution and spatial distribution of the extremely non-uniform electric field between the knife-plate geometry were obtained quantitatively. Finally

comparison between the experimental measurement and the Comsol simulation verifies the applicability and accuracy of the EFISH method. This method can be applied to the quantitative measurement of transient electric field in gas discharge excited by different sources.