We evaluated 45 cases of multiple myelomas retrospectively confirmed in Severance hospital from the period of 1983-1989, in order to assess the radiologic features of the multiple myeloma and to assist in possible early diagnosis and treatment. The results were as follows: 1. IgG(41%) was the most common immunoglobulin type secreted followed by light chain(36%), IgA(19%) and IgD(2%). Two percent of the patients had non-secretory type. 89% of patients were in their stage III of the disease. 2. Among the 45 patients, 96% had anormal plain radiographic findings with average number of 4.5 lesions. Common sites were the spine, rib, skull, pelvis, and humerus in descending orders. The findings were localized or diffuse osteolytic bone destruction(85%), osteoporosis(49%), pathologic fracture and endosteal scalloping(55%). Osteoporosis was more prominant in stage III than stage II. 3. Both plain Z-ray and radioisotope study was available for comparison in 28 patients. Concordance betwee the two studies were 44%, lesions detected only on plain X-ray film were 51%, and lesions detected only on the radioisotope were 5%. The plain radiography was able to detect only 54% of bone lesions confirmed by bone marrow biopsy. With the above results, accurate evaluation of bone lesions in multiple myeloma may be difficult with radiologic studies only. But familiarity with these radiologic findings of this disease entity is necessary for early suspicion of the disease, thus for early deagnosis and treatment.