Abstract: Objective: In order to clarify the smoke control effect of different smoke exhaust design schemes in the underground single train parking line distribution section (simplified as SLS) of rail transit engineering, and to determine the factors affecting the overall smoke exhaust capacity and airflow organization distribution in the tunnel section, the on\|site implementation of smoke exhaust effectiveness in the SLS is required. Method: A SLS in an operating urban rail transit line is selected, and 6 different test conditions are set up to address the key factors affecting the overall smoke exhaust capacity and airflow distribution in the tunnel section. Onsite cold smoke testing is carried out to measure the sectional wind speed, smoke flow direction, and actual smoke exhaust effect of each scenario, and the test results are analyzed. Result &Conclusion: The smoke exhaust capacity of the ventilation shaft system mainly depends on the number of TVF (tunnel ventilation fan) turned on, and the jet fan mainly plays the role of airflow distribution. Through the reasonable combination of TVF and jet fan, an effective smoke exhaust airflow organization scheme can be formed. A jet fan should be installed in the single train parking line area to distribute airflow among the various lines in the area, ensuring that the wind speed in the ignition zone meets the regulatory requirements. It is not that the more jet fans are opened, the better the ventilation effect is. Only turning on the jet fan in the tunnel corresponding to the fire location has the advantages of high longitudinal wind speed and simple control. It is recommended to install two sets of jet fans in the SLS, and the interval between two sets of jet fans should not be less than the length of one train.