Аннотация:The principal factors that control the character of deformation variations in water level in mouth
areas of rivers are considered. The role of wind regime and the sea level variations in the formation of positive and negative setups is assessed. River mouth zones are classified in terms of the predominance of positive or negative variations in water level. Specific features of the positive or negative setup regimes in the mouth zones of the Neva, Don, and Volga rivers are discussed.