Abstract: The paper discusses the principles of developing a hierarchical system of units for zoning the coastal zone and shelf of the World Ocean based on bionomic (ecosystem) features are discussed. A number of scientific and applied problems require zoning of ecoregions (sea basins) at the regional and topological levels. A system of units is proposed, taking into account the zonal, depth-related, and azonal features of ecoregions. The main initial unit of bionomic zoning is the underwater landscape. As an example of regional and topological zoning, the morphological structure of landscapes of three districts of the Japanese coastal region of the Sakhalin orogenic region of the Japan Sea is considered. The hierarchical system of units of bionomic zoning makes it possible to identify landscape analogues. In practical terms, this zoning may help to predict the introduction of useful species and forecast the risk of invasion by harmful species.