Radiographic and scintigraphic analysis of osseous system were performed in 152 cases of metastatic bonetumors with definite primary sites of malignancies. (11 cases with radiographic analysis alone) Bone involvementby hematologic malignancies was not considered in this study. The result was as follows: 1. Among total of 152patients, 100 patients were male and 52 patients were female. 2. Regarding age distribution, 6th decade was thepeak and 5th to 7th decades were the majority. 3. Among total of 141 patients who underwent both bone scintigraphyand conventional bone radiography, 70 patients were scintigraphically positive and radiographically negative. Only2 patients were scintigraphically negative and radiographically positive. 4. Lung cancer was the leading cause(52cases, 34% of all metastatic bone tumor) and stomach cancer(20 cases, 13%), breast cancer(17 cases, 11%), prostatecancer(11 cases, 7%) and hepatoma(10 cases, 7%) were in the decreasing order of causes. In male, lung cancer wasthe leading cause of metastatic bone tumor (44 cases, 44%). Prostate cancer(11 cases, 11%), stomach cancer (11cases, 11%) and hepatoma(10 cases,10%) were in the decreasing order of causes. In female, breast cancer wasleading cause(17 cases, 33%) and stomach cancer (9 cases,17%) uterine cervix cancer(8 cases, 15%) and lungcancer(8 cases, 15%) and lung cancer (8 cases, 15%) were in the decreasing order of causes. 5. The ribs, spine andpelvis were most commonly involved. Skull, femur and humerus were also involved frequently. Metastasis distal tothe knees and elbows occurred less frequently(8 cases,5%). 6. Osteolytic metastasis occurred most frequently(56cases, 68%). Osteoblastic metastsis(1 cases, 16%) and mixed metastasis(8 cases, 10%) occurred less frequently.Among total of 61 patients with osteolytic metastasis, lung (29 cases, 33%), stomach (8 cases, 13%), breast(7cases, 11%) and liver(7 cases, 11%) were the frequent primary sites of decreasing order. Among total of 16patients with osteoblastic metastasis, prostate(6 cases,38%), lung (4 cases, 25%) and stomach(2 cases, 13%) werefrequent primary site of decreasing order. Among total of 10 patients with mixed metastasis, breast(3 cases, 30%),stomach(3 cases, 30%) and prostate(2 ases, 20%).