The results of complex study of the ice core at Vostok station (Antarctic Continent, the drilling hole 5G) are presented. The chemical analysis has shown a correlation between the ion composition of the ice core water and paleoclimatic signals. Maximal concentration of the dissolved matters (up to 600 g/l) in ice corresponds to the last maximal glacial period (the ice age is 22 000 years). During "warm" periods (MIS 1; 7500 years) and (MIS 5e; 126 600 years), a minimum of dissolved matter is observed (200-400 μg/l). Comparative analysis of the results with available data of international investigations has shown a possibility of formulation and successive solution of problems of the complex analysis of ice cores in the polar regions of the Earth.