Abstract:For the pre-stack depth migration from undulate surface,Kirchhoff method can deal with the undulate surface flexibly but fail to image very complex substructures accurately.Hybrid wave equation method can image very complex substructures accurately but is difficult to handle the undulate surface.The paper finished the hybrid wave equation pre-stack depth migration in a condition of undulate surface so that achieved the goal that we can both image complex substructure accurately and handle freely undulate surface. The pre-stack depth migration beginning from undulate surface includes the correction of surface elevation implicitly in itself,which is more accurate than the conventional method because the former carries out the elevation correction along the real wave propagation path in medium and the latter only is vertical static time shift,neglecting horizontal component.