Abstract <p>The paper offers spatial and geochemical characteristic of poorly studied soils of the Barents Sea coast which is an important element in the development of the theoretical basis of soil science (including its system of taxonomic units and criteria for their diagnostics) and a necessary condition for rational nature management. Morphological and preliminary physicochemical characteristics are given, and the genesis of soils developing at different distances from the coastline (tidal flats, sandy-pebble bars, marshes of different levels, ecotone (maritime) zone, and watershed) is described. The most important patterns of spatial distribution of organic carbon and nitrogen reserves in the soils of the territory have been identified. In saline marsh soils formed under periodic flooding by tidal and storm surge waters, carbon stocks to a depth of 1 m amount to 300–700 t/ha, and in watershed tundra soils receiving marine aerosols, they reach up to 1300 t/ha. Nitrogen reserves of coastal soils range from 14 to 50 t/ha. Proposals for the systematic position of coastal soil groups have been put forward for inclusion in the current classification of Russia’s soils. It is deemed necessary to single out the following types: saline marsh soils formed under conditions of periodic flooding by tidal and surge seawater; maritime soils, which are only affected by the sea through the deposition of sea aerosols and/or infiltration of groundwater, and which have the specific characteristics of fresh marine sediments; and soils of river deltas and estuaries in the river-sea interface zone, which are additionally affected by the riverbed processes.</p>