A three-module marshaling model for a 100% low floor light rail vehicle with longitudinal coupled side-motor drive bogies was built by using the multi-body dynamics simulation software SIMPACK. The main plenum, orifice, and additional plenum of the central suspension air spring were modeled by MATLAB/Simulink. The operating conditions of the 100% low-floor light rail vehicles were set, and the feasibility of using air springs in the 100% low-floor light rail vehicle were analyzed by co-simulation combining SIMPACK and MATLAB/Simulink. The results indicated that both the vehicle stability and curve passing ability are improved after using the air spring. Specifically, the critical speed of hunting instability is increased to 149km/h, which is higher than the design speed. Both the stability and the maximum acceleration index are less than 2.5 as the vehicle runs. When the vehicle passes through a small-radius curve, all the wheel load reduction ratio, derailment coefficient, wheel lateral force, and wheel rail lateral force are less than the evaluation standard limit, and all the performance indices meet the technical standards of this type of air spring. Therefore, the application of air spring to the 100% low-floor light rail vehicle is feasible.