The increased number of extreme marine events is one of the most serious hazards to coastal areas around the world. The study of the impacts of marine events on coastal lakes has enabled us to gain important insights into the coastal ecosystem’s response to these events. On the Baltic Sea southeast coast as a result of studying Lake Lipovskoye and Lake Beloye on the Kurgalsky Peninsula obtained data on hydrology and hydrochemistry of the lakes, structure of lakes’sediments, the distribution of macrophytes and features of the vegetation reflection in the lakes’surface sediments based on pollen data. Bathymetric maps of lakes and their watersheds were constructed. Our complex studies confirmed the lakes’ uniqueness. According to hydrochemical data, Lake Lipovskoye has mesotrophic status and is classified as brackish water, whereas Lake Beloye is oligotrophic and freshwater. It was found that the lakes are characterized by small values of specific catchments – 10.3 for Lake Lipovskoye and 2.7 for Lake Beloye. Subrecent pollen spectra of lake surface samples quite adequately reflect modern aquatic vegetation, especially the communities of submerged hydrophytes in Lake Lipovskoye and floating hydrophytes in both lakes. Potamogeton (P. pectinatus L., P. perfoliatus L.) and Myriophyllum sp. are dominants in the pollen spectra and modern aquatic plant communities in the lakes. Over a short-term period, there are substantive differences in the species composition and dynamics of macrophyte pollen for both lakes. The study of lake sediments found a link between the Holocene sedimentation in Lipovskoye and Beloye lakes and the Baltic’s transgressive and regressive stages (Ancylus, Littorina, and Baltic Ice Lake stages).