Based on the theory of aero-elasticity, the governing differential equations of a high-speed train model with seventeen degrees of freedom are derived under the supposition of quasi-steady aerodynamic force. Eigenvalue theory is used to investigate the critical hunting velocity. The influence of aerodynamic force on critical hunting velocity and curve negotiation performance is analyzed. The limit cycle responses of the nonlinear system with flange forces and aerodynamic forces are studied using the numerical integration method, the results of which show that the effects of aerodynamic forces on lateral stability, curve negotiation performance and limit cycle oscillation of high-speed train are quite obvious.