Abstract: Objective To evaluate the efficiency and safety of loading dose of Ibandronate in the treatment of metastatic bone pain (MBP) induced by malignant tumors. Methods Eighteen patients with malignant tumor who were to be in our hospital and treated with Ibandrnate were analyzed retrospectively. Ibandronate was administered intravenously 4mg per day at loading dose in more than 30min for 4 consecutive days. Onset time, pain score, KPS score and daily morphine consumption were recorded. The serum markers such as calcium, creatinine were monitored. Results Eighteen cases were eligible to evaluate the efficiency and safety. Among them, the pain of 13 cases (72.2%) was relieved. The average onset time was (3.7±0.8)days. The pain score was significantly decreased after treatment and the life quality of patients was markedly improved (P<0.05). The morphine consumption was reduced by about 20mg to 60mg in 4 cases after treatment. The adverse reaction was relieved and no renal toxicity was observed. Conclusion Administration of loading dose of Ibandronate had quick onset time and mild side effects. It could significantly relieve metastasis bone pain and improve KPS, reduce the morphine consumption dose, avoid morphine-induced side effect, and effectively decrease serum calcium level.