Mineral waters containing fluorine (fluorinated waters) at a concentration in excess of 1 mg per liter are extensively used in the newly developing spa and health resort areas of the Russian Federation. They have been found in Siberia, Trans-Baikal regions, and the Krasnodar Territory (together with the Greater Sochi). These waters are mainly used for drinking as a component of the balneotherapeutic treatment. In this context, the study of the therapeutic effects of low-mineralized hydrocarbonate-sodium waters containing fluorine in high concentrations is of paramount importance for the substantiation and facilitation of their external application in the framework of the programs of combined spa and health resort-based treatment of various diseases. We have investigated the possibility of the external application of «Plastunskaya» mineral water characterized above all by the high content of fluorine for the external treatment of osteoarthritis in 187 patients at the age varying from 37 to 63 years in the combination with the sparing regimen of physical activity, therapeutic physical exercises, klimatotherapy of moderate intensity, and a balanced diet. The patients were prescribed to take general «Plastunskaya» mineral water baths with the fluoride concentration of 7.4 mg /l at a temperature of 36 C from 7 to 15 minutes in duration for 2 consecutive days with a break on every third day (the total course consisted of 14—16 baths). It was shown that the combined treatment with the use of fluorine-containing mineral water resulted in the significant improvement of the clinical and biochemical parameters characterizing the health status of the patients suffering from deforming osteoarthrosis.