Fewer geophysical methods can be utilized in marine project exploration than in the land. Seismic reflection is the preferred geophysical choice. When the submarine sediments are contaminated by shallow gas, the shielding effect of acoustic signal leads to the failure of seismic detection. In this paper, the high density DC resistivity method was adopted to investigate the submarine sedimentary strata as well as the underlying bedrock. The forward and inverse model was built and calculated based on the resistivity borehole logging data, a shallow onshore engineering with this method was conducted and the results show satisfactory results in the submarine engineering exploration. In some parts of the area where seismic reflection works effectively, the authors explained the geology with comprehensive methods, which could ensure the reliability and improve the accuracy of the interpretation.