A 60-year-old woman was given a diagnosis of Churg-Strauss syndrome (CSS) in 2000 because of peripheral blood eosinophilia, eosinophilic pneumonia, asthma, polyarticular pain, and limb numbness. She was treated with prednisolone (PSL), and the above symptoms improved but then relapsed on tapering of PSL. In September 2009, after 7 days of tapering of PSL to 5mg/day, the patient developed a subarachnoid hemorrhage and was admitted. MRA and cerebral angiography revealed no aneurysm; the source of bleeding could not be determined, but her symptoms indicated a benign course. A chest X-ray 27 days after admission showed left diaphragmatic elevation, and left phrenic nerve paralysis was diagnosed by a phrenic nerve stimulation test. Peripheral blood eosinophilia had progressed gradually during the admission period, and although it is rare for subarachnoid hemorrhage and phrenic nerve paralysis to be associated with CSS, we regarded these as vasculitis symptoms related to CSS.