In cases with advanced head and neck cancers, bony metastases cause skeletal-related events （SRE）, such as pathological fracture, spinal cord injury, and pain, affecting performance status （PS）. Previously, the treatments for SRE were surgery, radiation therapy and administration of bisphosphonate formulation with anti-tumor effects. However, in Japan in 2012, denosumab, a fully human monoclonal antibody against the receptor activator of nuclear factor-kB ligand （RANKL）, was approved and expected to be used as a new medication for the treatment of bony metastasis. Anti-bony metastasis medications have been used for the prevention and alleviation of SRE and not for their anti-tumor effects. Recently, reports about the anti-tumor effects of denosumab have increased. Here we report a clinical presentation of the significant effects of denosumab in a case of olfactory neuroblastoma with bony metastasis.