The aim of the study was to investigate urolithiasis prevalence in the main administrative regions of Tadzhikistan, to ascertain effects of drinking water quality, water pollutants and other environmental factors on urolithiasis morbidity in endemic regions of Tadzhikistan. It was found that high urolithiasis incidence rate in some regions was associated with high water pollution (class III and IV), its high natural mineralization and hardness, high content of chlorides, sulphates and other components of salt composition, organic and non-organic pollutants. Chemical and microbiological tests showed that sanitary standards were not strictly observed in the regions with high urolithiasis morbidity. These regions are also characterized by high incidence of acute intestinal infections, thyphoid, nephropathies, high environmental pollution, high density of population.