Abstract: As one of the important indexes to predict coal and gas outburst, it is of great significance to study the influence factors of the initial velocity of gas emission. Based on the analysis of the main factors affecting the initial velocity of gas emission such as metamorphic degree, inflation pressure, temperature, pore characteristics, particle size, water content, external sound field and electric field, the research progress and shortcomings of each factor condition are pointed out, and each influence factor is summarized as three aspects: gas content, gas pressure and pore properties. The problems about the initial velocity of gas emission that need to be solved are analyzed and proposed, and it is concluded that the research on the coupling effect of multi-factor of the initial velocity of gas emission is the main development direction.