The Ocean Bottom Node (OBN) seismic exploration technology has gradually become an important technical means in offshore oil and gas exploration. It is not constrained by ocean bottom cables and can collect high fidelity and wide azimuth multi-component data, making it easy to study PS wave information. Making full use of the field data of seismic exploration and finely studying the joint inversion method of P-wave velocity and S-wave velocity is the key research direction in this field. However, due to the special observation mode of OBN technology, the problem of inconsistent elevation of shot-receiver points will occur in the processing, and the conventional migration imaging method will not be able to be used. In this paper, the wave equation datum correction method is combined with the conventional migration method, which can effectively solve the problem that the shot points and receiver points are not in the same datum. At the same time, in the process of velocity update, the PP and PS wave layer depth residual constraint is introduced into the P-wave and S-wave tomographic inversion to constrain the update of S-wave velocity, and realize the P-wave and S-wave joint tomographic velocity inversion method of multi-component data of ocean bottom nodes, which provides accurate velocity field for subsequent migration imaging processing.