In this paper, motion stability of the high-speed maglev vehicle under steady aerodynamic load was studied. The dynamic model of the high-speed maglev vehicle on the curved guideway considering influence of aerodynamic loads was established. The critical speed concept of the maglev vehicle considering aerodynamic loads’ effect based on eigenvalues was presented. Vehicle speed, control parameters, and aerodynamic coefficients to make the critical speed of the high-speed maglev vehicle change in the critical state were also analyzed .?The results show that when the system reaches the critical state, it has two critical speed.?Under the conditions in the critical state, the position control parameters varys from 20000KN/m to 2000KN/m, and aerodynamic coefficients varys from 0.006 to 0.001, the critical speed gets larger.?The first critical speed occurs when the aerodynamic force is upward, and the second critical speed occurs when the aerodynamic force is downward.?Instability is caused by the change from the equilibrium position for the curved guideway and wind loads.?Aerodynamic down force and centrifugal wind loads is not good for stability, but aerodynamic lift force and centripetal wind loads improve stability. The horizontal angle can be matched with the centripetal force, but the vertical angle is allowed to be set in a small range.