The relevance of the study is caused by the need to research hydrogeochemistry of the territory because of the planned large-scale production of coalbed methane. The main aim of the research is to study general hydrogeological and hydrogeochemical features of Naryksko-Ostashkinskaya area, conditions of groundwater supply and unloading, to pay special attention to ash value of water chemistry and genesis (using data on the isotopic composition). The methods used in the study: To carry out a complete chemical analysis of water the authors have used traditional methods as well as methods of spectral, atomic absorption analysis, etc. 18O and 2H(D) of water samples were measured by isotope equilibration applying universal system of preparation and introduction of GasBench II gas samples on mass spectrometer DELTA V ADVANTAGE. The results: The chemical and isotopic analyzes have shown that only infiltration water with local supply areas, with different salinity degrees are developed over the area. The active and slow water exchange zones were singled out. Within the first (top) neutral zone fresh CaHCO3 water is developed. Within the area of slow water exchange (including coals) alkaline HCO3Na (soda) water with salinity to 19 g/l is developed. Water salinity grows with depth mainly due to HCO3 - and Na+ ions, rare due to SO4 2- and Cl- ions. In water of a lower part of the slow water exchange the "oxygen shift" is observed due to isotopic exchange with the rock as a result of greater interaction time in the system water-rock.