We report a case of successful high-dose intravenous immunoglobulin (IVIG) use in a patient with refractory polyarteritis nodosa (PAN). Treatments with prednisolone (PSL) and various types of immunosuppressants including methotrexate (MTX) and intravenous cyclophosphamide (IVCY) were unsuccessful, and then, high-dose IVIG therapy was added. High-dose IVIG therapy improved all symptoms including high fever, arthralgia, mononeuritis multiplex and indurated erythema due to PAN. Moreover, serum inflammatory markers were also normalized. High-dose IVIG is maintaining complete remission for PAN without flare-up for additional 4 years. Therefore, high-dose IVIG therapy might be considered as a first-line therapy in patients with PAN or alternative therapy in refractory PAN.