The article is devoted to the results of the new historical investigations concerning the functions of Navy Forces on the Baltic Sea in interwar period. The military authorities of all particular states of Baltic region have had quite different conceptions of their own Navy Forces development at that time in case of some serious military conflict. Enough important influence of such differences may be certified to the objective reasons, concerning the state of Baltic Sea as close area sea, as well as to economic and military potential of each particular state in Baltic region.