Abstract: In terms of compound dynamic disaster in depth high-gas mine, in order to investigate the influence rule of coal and rock mechanical behavior by gas pressure, a set of experimental equipment for testing coal samples deformation and failure under uniaxial compression condition of coal and rock containing gas was developed with the RMT-150 C rock mechanics test system as a carrier, and then, constituted a gassy coal uniaxial compression experiment system with XL2101 C SPC static resistance strain gauge.Outburst-proneness index determination tests were conducted on this system.The results showed that 1) the volume-expanding phenomena of coal samples occur with the increase of gas pressure during the process of gas filling and adsorption.The volume change of coal samples is divided into two stages:the accelerated deformation stage and the gentle stage; 2) with the increase of gas pressure from 0 MPa to 2 MPa, the dynamic failure time of coal samples decreases by 547.64%, the elastic energy index, impacting energy index and compressive strength of coal samples decrease 85.29%, 96.24% and 58. 78% respectively. The comprehensive evaluationresult is a decrease in impact tendency.