This study presents the use and effects of a low mineral content water called "Monteferrante" on patients with urinary stone disease. We evaluated the blood and urine sample of twenty stone formers and ten healthy volunteers at three and six months after "Monferrante" water intake. Besides a benefic increasing of diuresis, the results show: an increase of: urinary magnesium (p < 0.001), urinary calcium (p < 0.01), uricosuria (p < 0.01), and reduction of: blood uric acid (p < 0.01), blood sodium (p < 0.05), azotemia (p < 0.05) and cholesteremia (p < 0.01). The "Monferrante" oligomineral water can be considered as an efficacy presidium in the prevention of stone disease.