The chemical composition of 29 of the bottled mineral waters available in the Spanish market are analyzed, including composition of the tap water supplied by Canal de Isabel II, which provides drinkable water to Madrid with a population close to 5 million inhabitants. The literature relevant to the influence water and its composition may have on the lithiatic prophylaxis is reviewed, exploring data related to our waters, and offering an approach on their use in the different types of lithiasis.