Abstract: In order to study the influence of coal fine particle size on propagation characteristics of coal and gas outburst shock wave, a set of outburst fine coal-gas two-phase flow simulation experiment system was independently developed, and outburst simulation experiments under different coal fine particle size conditions were carried out. In the process of outburst, the variation of shock wave overpressure with time in different positions of simulated tunnel was monitored in real time. The experimental results show that the shock wave overpressure presents a pattern of alternating positive and negative pressure phases at each monitoring point, the peak value of the shock wave overpressure is positively correlated with the particle size of the coal in the outburst cavity; the propagation speed of the outburst shock wave in the tunnel is also affected. The impact of the particle size of the pulverized coal, that is, the smaller the particle size of coal fine, the smaller the shock wave propagation velocity, and the shock wave propagation velocity shows a decay trend along the roadway.