A 45-year-old woman was hospitalized because of systemic edema and peripheral nerve impairment. The patient had complications of organomegaly, endocrinopathy, and monoclonal gammmopathy, and was diagnosed with POEMS syndrome based on these characteristic signs and symptoms. Interleukin-6 (IL-6) and vascular endothelial growth factor (VEGF) levels in the serum and ascitic fluid were high. Many of the patient's symptoms were ameliorated, and IL-6 and VEGF levels in the serum and ascitic fluid decreased slightly during chemotherapy, but she died of respiratory failure. Autopsy revealed severe systemic edema and macroscopic hemorrhage in many organs, but VEGF and IL-6 producing cells were not found.