Biophosphonates are analogues of pyrophosphate. The mechanism of action of bisphosphates is the inhibition of osteoclast activation (antiresorptive mechanism). The oral bioavailability of biophosphonates is only about 1-2%, and because of gastrointestinal side effects (mainly esophageal irritation), oral agents are less useful in oncology. Biophosphonates are used for the treatment of Paget s disease of bone, the prevention of osteoporosis, and in another clinical scenarios as the prevention of bone disease after organ transplantation. In clinical oncology biophosphonates are used for the treatment of hypercalcemia of malignancy, prevention and treatment of bone events related to bone metastases, and in the prevention of osteoporosis related to breast cancer. According to American Society of Clinical Oncology (ACO) guidelines, biophosphonates should be used in hypercalcemia of malignancy and bone events related to metastases of breast cancer and multiple myeloma.