Abstract: To research the influence of different ventilation modes on the temperature distribution, CO concentration and smoke spread of the roadway, based on the fire simulation software Pyrosim, this paper studies the effects of Z, U, and Y ventilation modes on the smoke spread. Meanwhile, the influence of wind speed difference on flue gas counterflow distance and temperature in Y air inlet is studied. The research results show that the roadway temperature in the downstream area of different ventilation modes is in order U > Z > Y. For Z and U ventilation mode, the CO concentration reduces by 5.26% every 10 meters after 55 m away from the fire source point. The CO concentration of Y ventilation mode gradually stabilizes after 20 m from the intersection of the roadway. Under the Y ventilation mode, the wind speed of the downstream air inlet roadway has a certain effect on the upstream smoke backflow distance and temperature, the larger the wind speed is, the shorter the vortex extinction time is.