We analyzed the bone changes at each site of secondary hyperparathyroidism (2 degrees HPT) on hemodialyzed patients using both single photon absorptiometry (SPA) and dual photon absorptiometry (DPA). The subjects were 35 hemodialysis patients (12 male, 24 female) with 2 degrees HPT. The bone mineral densities (BMD) of 1/3 radius, head, total body and 3rd lumbar spine were measured before and after parathyroidectomy (PTX). Before PTX, the BMD of 2 degrees HPT patients were lower than the normal range of all sites, especially at the radius which mainly consisted of cortical bone. After PTX, the BMD at all sites increased especially in the head. The BMD of the radius also continued to increased up two years after PTX, but it was not as increased as the BMD of head. The BMD of the lumbar spine which consisted of cancellous bone mainly increased after PTX for one year and decreased thereafter. This decrease was influenced by age. There was a difference with the site of BMD after PTX. The determination of changes of BMD of head and radius was considered useful for the judgment of treatment.