Abstract: In order to realize the underground portable real-time monitoring of the vital signs of personnel and timely arrange rescue, a mine intrinsically safe watch was designed. Take NRF52840 low energy bluetooth chip as the control core, using GH3020 health monitoring IC + MPU6050 acceleration sensor + NST112x temperature sensor as the acquisition unit, combined with the power circuit design, to achieve vital signs data acquisition, BLE/Wi-Fi combined with high-precision RSSI technology to realize the rapid detection of device location signals. The Cortex-M4F core is used to provide efficient data calculation, compression, storage and remote transmission of data. The watch has the characteristics of high integration, good stability, high precision and low power consumption, and supports TCP/IP, ANT, Thread wireless communication and other protocols. After testing, the data acquisition accuracy, power consumption, sustainable working time and other indicators of the equipment have reached the productization standard, and are displayed on the PC in real time, to provide important protection for the life and health of miners.