Abstract: Under the different conditions of crushing experiments for outburst-prone and non outburst-prone coal,the relationship between particle size distribution law and specific surface area and crushing specific work was analyzed af- ter being pulverized coal sieve. The experimental results show that:the percentage of coal particles which are less than 0. 075 mm is very little,but there is a marvelous surface area;the quality ( < 0. 075 mm) of the distribution above a sieve which is the outburst-prone coal obeys the Gauss distribution,but the non outburst-prone coal obeys the normal distribution;the specific surface area increases with the increase of the energy under the same block degree,and the specific surface area of the outburst-prone coal is 1-2 times of the non outburst-prone coal under the same energy;the new surface area increases exponentially with the increasing of energy,but the increasing rate decreases with the in- crease of the energy. This research can reveal the relationship between coal materials after crushing the distribution of particle size and crushing energy,to provide the experimental basis to the energy dissipation of analysis in the process of coal and gas outburst.