The article presents the history of development of the Laboratory for Hydrochemistry and Hydrogeology of the Northern Water Problems Institute (Karelian Research Centre, Russian Academy of Sciences) since its establishment within the Department of Hydrology and Water Management at the Karelian Branch of the USSR Academy of Sciences in 1953. For 70 years, the laboratory has been working to study surface waters, sea- and groundwater, atmospheric precipitation, bottom sediments. The history, the most important results, the main scientific achievements, and prospective lines for the development of hydrochemical research are covered. Special attention is givento the practical use of the results, as well as to the laboratory staff who have significantly contributed to its development.