The patient was an 85-year-old man who developed lung metastasis and intrahepatic bile duct cancer after undergoing surgery for kidney cancer. He had a 1-month history of persistent pain from the neck to both shoulders and proximal limb muscles prior to hospitalization. Computed tomography revealed no findings leading to the development of pain. The patient's condition did not improve despite the use of acetaminophen, immediate-release oxycodone, and kakkonto. Polymyalgia rheumatica (PMR) was suspected based on the clinical findings, with the erythrocyte sedimentation rate showing a marked increase at 107mm/h. As the diagnostic criteria were satisfied, a diagnosis of paraneoplastic syndrome with PMR-like symptoms was made. Accordingly, prednisolone administration at 20mg/day was initiated, which markedly reduced the pain. In cancer patients, pain that is not directly associated with cancer sometimes occurs. Paraneoplastic syndrome rarely occurs, and thus is relatively likely to remain undiagnosed. This is the first report of a case of paraneoplastic syndrome in a patient with kidney and bile duct cancers in Japan.