Abstract: The upgrade of PandaX-nT brings many new challenges to the electronics system, including more channels, high-speed and high-precision waveform digitization, flexible trigger algorithm and higher data bandwidth requirements. The readout electronics pre-research system was designed for the PandaX-nT dark matter direct detection experiment. The electronics system is mainly composed of pre-amplifier module, front-end digital module (FDM), data acquisition module (DAQ), and clock distribution module. FDM is composed of 8 channels 14 bit@1 GS/s ADC. And it can digitize the detector signal waveform and communicate with DAQ through optical fiber. DAQ is mainly designed for data collection from FDMs and implementation of trigger algorithm. DAQ communicates with the computer through Gigabit Ethernet based on TCP protocol, which guarantees the reliability and stability of data transmission. The electronics has high expansibility and can implement more complex trigger algorithm, which can meet the needs of next generation upgrade. The design and functional verification of the system were completed and the preliminary commissioning tests with the detector were conducted, which indicates the system functions are good.