Abstract: Put forward a new method for long-span bridge buffeting analysis which using quasi-steady aerodynamic stiffness and unsteady aerodynamic damping based directly on wind tunnel test. The wind tunnel test of bridge Segment model shows that the new aerodynamic model can describe the aerodynamic stiffness and damping properties of bridge structure more accurately. As an example, both the numerical results of the new model and traditional flutter-buffeting model were presented and compared for East Sea Bridge under wind loads. The computed results and wind tunnel test results show that the new model gives accurate outcomes and has explicit physical meanings.