The Ocean-Bottom Nodes (OBN) seismic exploration technique can not only obtain all-dimensional fidelity data, but also improve the repeatability of 4D exploration and the reservoir monitoring results. The multi-component seismic data acquired by OBN seismic exploration contains P- and S-wave information of marine sediments, which provides abundant data for offshore oil and gas exploration and reservoir monitoring. In this paper, in order to obtain the velocity distribution of sediments and provide a basis for migration velocity modeling and oil and gas identification, based on OBN seismic data, linear traveltime interpolation ray tracing forward algorithm and particle swarm optimization nonlinear inversion algorithm are comprehensively adopted to perform joint inversion of P- and S-waves. A theoretical model is first created to verify the validity and adaptability of the inversion algorithm, and then the joint inversion of actual OBN data is carried out to determine the P- and S-wave velocities. The experimental results of theoretical model and actual OBN data test show that the method is feasible, and the joint inversion of P- and S-wave velocity using the method has high accuracy. [ABSTRACT FROM AUTHOR]