Abstract: With the boost of environmental protection requirements and the continuous pursuit of production efficiency, the efficient and safe operation of coal power supply system is directly related to the production safety of coal, and is an important link to ensure the continuity of production in the mining process.In addition, the coal mine environment is unique, with special conditions such as dust, high temperature, and high humidity, which puts higher demands for the coal power supply monitoring system.The traditional coal power supply monitoring system has disadvantages such as complex wiring, limited communication distance, and unstable data transmission.This article designs a coal power supply monitoring system based on LoRa and ESP-NOW,aiming to improve the reliability and coverage of the coal power supply monitoring system.The system selects STM32 microcontroller as the main control chip, uses LoRa networking technology, introduces ESP-NOW protocol, and constructs a low-power, long-distance transmission wireless sensor network to achieve real-time monitoring of the operation status of coal power supply system.The experimental results show that the system has significant advantages of high data transmission reliability, long transmission distance, and low power consumption.