Abstract: The mining refuge chamber must be monitored O2, CO, CO2, CH4, temperature, humidity and other environmental parameters. According to the requirements of China, it must be ensured that not less than 2 hours of standby time of coal mine safety monitoring system after AC power failure according to the conventional coal mine safety monitoring system requirements, and the standby time of refuge chamber monitoring system must ensure not less than 96 hours without AC power, more stringent and longer time requirements is proposed to the standby power. The national standards for explosion proof of GB3836 allowed only using nickel-cadmium battery and potentially nickel-hydrogen battery in explosion-protection cavity, and there are disadvantages of low voltage and small capacity, it is not suitable for high power applications. This design according to the characteristics of distributed monitoring system equipment proposed distributed standby power supply structure, design a small power intrinsically safe backup power, and it was installed between the intrinsically safe power supply output terminal and the intrinsically safe apparatus. Test results show that the new intrinsically safe backup power has safety monitoring equipment to provide standby power supply for a long time, battery with the use of high efficiency, small volume, light weight, cheap price, provide safe and reliable power supply for refuge chamber monitoring system.