The results of the estimation of the limiting sizes of oil and gas fields profitable for development in different geographic-economic and climatic conditions of Russia’s water areas are given, the influence of the various factors (nature-climatic, mining-geological, geographic-economic and sea depth) on a degree of their development economic efficiency is determined. The received accounts are a basis for the choice of prime directions and objects of sea exploration and can be used in creating the strategy of study and development of Russian continental shelf oil and gas potential as well as programs of oil and gas offshore licensing.