Abstract: Secondary electrostatic discharge(SESD) is an electrostatic discharge phenomenon that occurs between tiny gaps in an electronic device and has a peak current of several tens of amperes, which can cause fatal damage to many components such as transistors. The circuit-level simulation model composed of electrostatic discharge (ESD) simulation circuit, secondary discharge simulation circuit and current target circuit is used to study the secondary discharge process and parameter such as discharge waveform. The waveform of the secondary electrostatic discharge is initially explored and compared with the initial model to verify the known theory. Secondly, based on the methods of experimental research and data analysis, the characteristics, peak characteristics and time delay characteristics of the secondary discharge waveform are summarized. It is found that the peak current of the secondary discharge is larger than the first discharge current, and the time delay of the secondary discharge is normally distributed. The results of this study are consistent with and validated the current theories of microscopic process in SESD.