In response to the problems of car slippage, wall peeling, and ground mold caused by condensation in underground garages, taking a garage in Handan as an example, the actual monitoring data was analyzed. Fluent software was used to simulate the installation of an air curtain system in the garage, set different air supply speeds, observe the temperature and humidity cloud map of the air inside the garage, and compare and analyze it with the temperature and humidity inside the garage under natural ventilation conditions. Preventive measures and ventilation operation strategies were proposed. The simulation results show that when the air supply speed of the air curtain system is 2 and 4 m/s respectively, the air temperature in the garage increases by 0.7 ℃ and 1.2 ℃ respectively, and the relative humidity decreases by 5.5% and 8.9% respectively, and the dew point temperature decreases to 13.92 ℃ and 13.73 ℃ respectively; When the air supply speed increases from 4 m/s to 6 m/s, the change is consistent with the increase in wind speed from 2 m/s to 4 m/s. In this case, the dew point temperature decreases to 13.52 ℃, which is 14 ℃ lower than the wall temperature and 15 ℃ lower than the ground temperature, and the anti-condensation effect is significant.