The use of groundwater in population water supply systems gains more and more importance because of increasing degradation of the quality of surface water sources. At the same time there are changed concepts on ubiquitous high quality of groundwater. The executed analysis offoreign and domestic literature allowed authors to determine the character and causes of negative changes in the composition of groundwater. In the large body of investigations there were established cause-and-effect relationships between a number of noninfectious (including cardiovascular and cancer) and infectious diseases and anthropogenic pollution and the natural composition of groundwater. In the article there is substantiated the formation of a new interdisciplinary scientific direction - medical hydrogeology. On the basis of current data on the medical and ecological significance of the quality, quantity and regime of the groundwater, geological conditions of the shaping of their composition, there was shown the need of the consideration of the hydrological situation in making water supply management solutions safe for the health of the population. In this regard, there were considered the interrelationship and interdependence of allied disciplines - hygiene, ecological toxicology and epidemiology, hydrogeochemistry, hydrogeology. There was pointed the importance of the acquisition of based on hydrogeology medical specialists of the water supply profile for sharing with hygienists of the effective solution of tasks of the management of groundwater sources.