The integration of seismic survey method with shallow layer profiling method, single-channel reflection method and multichannel reflection method has broad application prospects in the field of offshore engineering geophysical exploration. This paper describes the respective emphases of these three methods and the complementary relationship between these methods and, with the practical example of Shenzhong passageway, expounds the technologies of marine seismic data acquisition, data processing and data interpretation. The engineering application results show the multiple reflection wave technology is an effective supplementary means in the exploration of submarine tunnels, river-crossing channels and sea-spanning bridge locations. It can provide basic data for offshore water area engineering and is also fairly effective in the precise layering of strata and the detection of concealed structures.