Abstract: Focusing on the coal-gas two-phase flow in the process of coal and gas outburst,the experimental study on outburst coal-gas two-phase flow in roadway is carried out by using self-developed dynamic effect of coal and gas out-burst simulation test device. According to observations,the movement of coal particles in the test can be divided into acceleration stage,balance deceleration stage and settlement stage. The mathematical model of the movement of the outburst coal in the roadway is established by combining the suspension motion mechanism and the conservation of en-ergy law of the solid particles in the airflow. Through the model calculation and analysis,the migration distance of the coal particles increases with the increase of the initial air velocity. Due to the different flow states,the law that the mi-gration distance varies with the particle size is different. The mathematical model provides a quantitative analysis meth-od for the engineering calculation of coal-gas two-phase flow of coal and gas outburst.