Abstract: A multi-channel online high-density electrical method instrument system for mining based on ARM and FPGA is designed to address the limitations of narrow application range and low automation level of current centralized DC electrical method instruments in coal mine hydrogeological exploration. The system features a six channel electrical method instrument substation, which uses a high-performance ARM processor to transmit electrical data and control signals. A 24 bit AD and FPGA programmable logic chip are used to perform high-precision sampling and parameter configuration of on-site electrode signals. An intrinsic safety high-voltage drive circuit is designed at the electrical method instrument substation through an IGBT circuit. The main control circuit of the electrical method instrument slave adopts a low-power microprocessor STM32L431, and a micro relay is used to control the electrodes for flexible implementation. Configuration and control, ultimately achieving multi-channel automatic pole running operation. Through system software, the electrical instrument system can be remotely controlled to set parameters, collect sensor data, and perform data inversion in the coal mine environment, achieving the entire engineering application of geological exploration and mine water exploration. The actual test results of the system indicate that it has the characteristics of accurate data sampling, strong anti-interference ability, high application efficiency, and accurate data inversion results, which meet the needs of applying DC electrical exploration in coal mine hydrogeology.