Abstract: With a fluid numerical simulation software,the pressure balanced effect was simulated and analyzed.According to the principle and features of the pressu re balanced fire prevention and control technology and the relationship between the two end pressure variation and air leakage value of the pressure balance area,the p ressure regulated redundancy of the automatic control pressure balanced fire prevention and control system was determined.According to the frequent pressure regulati on,pressure regulated delay,low pressure regulated accuracy and other problems existed in the manual pressure regulation,based on the CAN bus communication proto col,a mine automatic control pressure balanced fire prevention and control system was designed.A detail design was conducted on the automatic control system of the air regulator.According to the delay of the air leakage pressure difference signal transmission,the Smith prediction with PID control and regulation method was applied t 0 regulate the air leakage and air pressure.Taking a mine in Shanxi as an example,the pressure balanced simulation results showed that before and after the pressure b alanced,the width of the spontaneous combustion zone in the goaf was reduced from 70 m to 20 m and the distribution of the spontaneous combustion "three zones" wa s changed from disorder status to regular status.