We report a case of a 37-year-old man with relapsing polychondritis and IgA nephropathy. He visited our hospital with high fever and the swelling of his ears and eyelids. His symptoms and the results of the biopsy of his right auricle fulfilled the Damiani's criteria. Laboratory examination on admission showed an increase of serum IgA level, a presence of immune complex, remarkable hematuria (grade III) and proteinuria (grade II). Most of his symptoms were improved by the administration of antibiotic and NSAIDs, however, urinary findings still remained unchanged. The biopsy of his right kidney led to a diagnosis of IgA nephropathy (group II). Although relapsing polychondritis is known to associate rarely with renal involvement, it is very rare to associate with IgA nephropathy. This case indicates that immune disorders including IgA nephropathy should be investigated in patients with relapsing polychondritis.