Abstract：In order to reveal the difference between ignition and line sources induced by fire and to achieve the mine fire prevention and control, this paper established the combustion model of coal mine fire based on the combustion characteristics of two fire sources by using the FDS. The fire smoke flow characteristics of the two type of sources were simulated and comparative analyzed in the same scene. Results show that under the condition of 1.2 m/s wind speed, horizontal velocity line fire is greater than the ignition source in the process of ceiling jet, and the length of the smoke back-flow is longer, and the maximum velocity of the cross section is 3.5 m/s near the fire source. Due to the throttling effect and restriction of the conveyer, wind speed decreases in the upper drift of the roof and the back of the conveyor. The throttle effect of the line source is more obvious. The decay rate of the line source is less than the ignition. The vertical temperature decreases gradually from the direction of the roadway roof to the floor. Therefore, the fire hazard of the line source is larger, and should be given more attention in the fire prevention and control.