The authors point out the therapeutic properties of sulphate-bicarbonate mineral waters. After summarizing the general mechanism of action of mineral waters, the main indications of such waters in thermal treatment are examined including: biliary sand, biliary dyskinesia, functional dyspepsia, irritable colon, chronic primitive constipation. The dysfunctions of biliary and digestive tracts are growing, mainly in the affluent world, because of the increase for stress, dietary habits, modern life style. Now they affect from 2,4% of general population to 7% of men and 20% of women, according to different studies. Mineral waters can improve symptoms and care some physiopathological underlying mechanisms. Authors stress the efficacy of sulphate-bicarbonate mineral waters in the therapy of biliary dyskinesias, namely gallbladder hypokinesia and Oddi's sphincter spasm, caused by their content in SO4 = anion and Mg++ cation and related effects on paracrine-endocrine gastrointestinal system. In addition, they report the effects of sulphate-bicarbonate mineral waters in the lithogenic bile (sand bile), because of their diluting and washing activity. Among the sulphate-bicarbonate mineral waters, the Authors outline the well-documented therapeutic activity of Acqua Santa and Fucoli of Chianciano Terme. Acqua Santa has stimulating effect on cholecystis's motility, as proved by controlled clinical trials. Finally, the therapeutic use of sulphate-bicarbonate mineral water is discussed in functional dyspepsia, chronic primitive constipation and irritable bowel syndrome.