Abstract: The refined analysis method was presented by consistent coupled method to compensate the coupling component between background and resonant modes.Then,the wind induced responses and mechanism analysis of 1.2 MW wind turbine tower-rotor system was evaluated in combination with the physical model of stochastic wind field and the integrated finite element model consisting of the rotor,the nacelle and the tower.The fluctuating wind velocity time series was simulated by the modified harmony superposition method and blade element momentum theory,which considering the blade-tower interaction.The calculation of wind-induced response of wind turbine system demonstrates the effectiveness and accuracy of the present approach.Finally the characteristics of background,resonant components and cross term between background and resonant responses of wind-induced responses were extracted.This paper proposed a new thought of analyzing wind-induced responses and mechanisms of actions for steel wind turbine system.