Paget's disease (PD) of bone is characterized by increase of bone resorption by atypical osteoclasts, followed by rapid new bone formation resulting in a disorganized mosaic bone. Although the pathophysiology is not fully understood, bisphosphonate, which is a potent anti-resorptive agent for treatment of osteoporosis, have been the most effective agents available for the treatment of PD. We report a case of PD of bone in a 49-year-old woman patient, who was treated with intravenous zoledronate.