Osteoporosis is characterized by a reduction in bone mineral density (BMD) . Reduced BMD has been reported in urolithiasis patients with hypercalciuria, as well as in those with normocalciuria. Bisphosphonates potently inhibit bone resorption and are used in the management of osteoporosis. We show the ability of bisphosphonate to prevent the recurrence of urolithiasis. Bisphosphonate reduced the excretion of urinary calcium and the ion activity product index of calcium phosphate in urolithiasis patients, and prevented urinary stone formation in long-term bed rest test. The results suggest that ALN not only improves osteoporosis but also reduces the risk of calcium stone formation. Bisphosponates are believed to reduce the urinary excretion of calcium by improvement of bone metabolism, and to have a direct effect in the prevention of urolithiasis.