The Jurassic-Cretaceous terrigenous complex of the Laptev and East Siberian Seas is of considerable interest as a potential exploration target. However, the key Jurassic and Cretaceous sections of the New Siberian Islands have been poorly studied. The results of this study were used to provide a detailed micropaleontological description of these sections and substantiation of the previous lithostratigraphic subdivision. We first identified a series of Boreal standard zones in the Jurassic and Cretaceous sections, based on the foraminifers, ostracods, dinocysts, and terrestrial palynomorphs. Our results, along with the published data on ammonites, bivalves, and terrestrial palynomorphs and the results of radiometric dating, provide more precise constraints on the stratigraphic position of the identified lithostratigraphic units. The results of this study can be corroborated by seismic data to explore offshore areas of the Laptev and East Siberian Seas. We also present detailed data on the geochemistry of organic matter from the Pestsovaya Formation (Hettangian-lowermost Upper Pliensbachian).