Abstract: The information of seismic amplitude and phase for reconstruction wave field can be used in waveform tomography inversion method to get a velocity model with higher accuracy and resolution theoretically. However, because of its serious nonlinearity and high dependence on initial velocity model, it often results in unsatisfactory inversion results in field application. This paper presents an improved strategy of multiscale inversion to establish higher?accuracy depth migration velocity field as an initial input model of waveform tomography, so that decrease the serious nonlinearity. This strategy is successfully applied to Marmousi model and case study, in which the updated velocity is used to make Kirchhoff pre?stack depth migration. The final result shows that the waveform tomography can retrieve much more high?frequency details and highly improve the accuracy and resolution of the seismic migration imaging