A case of multiple endocrine neoplasia type 1 (MEN 1) with a clinical manifestation of pyonephrosis is reported. A 47-year-old woman with a 14-year history of renal stones was initially seen with pyonephrosis. The patient was found to have elevated serum levels of parathyroid hormone and growth hormone. Radiologic examinations demonstrated an ectopic parathyroid tumor and a pituitary tumor. She was diagnosed as having MEN 1.