Analysis of the latest seismic data has shown that thick sedimentary basins are developed in the western part of the Laptev Sea and on the continental margin of the Siberian Platform. They are separated by a large basement high, the presence of which makes it difficult to compare sedimentary complexes on the continent and in a water area. An integrated analysis of geological and geophysical data on the continental margin of the Siberian Platform, the Laptev Sea, and adjacent folded structures was carried out. Furthermore, seismogeological models of sedimentary complexes on the continent and in a water area were constructed and correlated, potential fields were analyzed, and a structural map of the top of the crystalline basement was constructed. A comparative analysis of the geological and geophysical materials showed that the western part of the Laptev Sea is a northern continuation of the Siberian Platform and the oil and gas potential of this part of the sea will be associated mainly with the Upper Proterozoic–Paleozoic deposits.