A 68 years male, case of IgG type multiple myeloma ΙΙΙA was on Bortezomib and Dexamethasone. Patient was simultaneously receiving Zoledronic acid 4 mg in 100 ml normal saline over 15 minutes infusion once every 28 days. After 16 injections of Zoledronic acid, he had pain in left lower jaw. On examination he had bone loss in the lingual aspect of left mandibular alveolus near 1st molar tooth area. There was no discharge or swelling. Orthopantomograph (OPG) showed a large osteolytic lesion at the site of clinical inflammation. Histopathology of scrapings ruled out plasmacytoma. Our final diagnosis was Zoledronic acid related osteonecrosis of the jaw. Zoledronate was stopped.