Abstract: In the report, the membrane air spring for vehicles was used as the research object, and the nonlinear constitutive relation of hyper elastic material was used as the basis to study the contact nonlinearity, geometrical nonlinearity as well as the material nonlinearity of air spring. ABAQUS software was used to construct the lateral finite element model of air spring and calculate its stiffness characteristic, and the effects of cord parameters and the initial internal pressure on the lateral stiffness of air spring discuss were also discussed. The simulation result showed that the initial internal pressure and cord angle have a great influence on the lateral stiffness.