A total of 189 cases of primary bone tumors reviewed and analysed clinically and pathologically at the Department of Orthopedic Surgery, Presbyterian Hospital, Taegu, Korea during the 15 years period from july, 1964 to june, 1979. The results were obtained as follows: 1. In 189 cases of primary bone tumors, 87 cases (46%) were benign and 102 cases (54%) were malignant. 2. Osteochondroma was the most common benign bone tumor (31.0%) and followed by simple bone cyst (14.9%), enchondroma (14.9%) and giant cell tumor (13.8%). 3. Osteosarcoma was the most common primary malignant bone tumor (45.0%) and followed by fibrosarcoma (17.7%) and chondrosarcoma (12.8%). 4. 22 cases were solitary and 5 cases were multiple Iesions of osteochondroma. The knee joint area was the most common site of osteochondroma (59.2%) and peak incidence was in the second decade. 5. Simple bone cyst was 13 cases. The sex distribution of simple bone cyst showed 5.5 times of the male predominence. The knee joint area was the most common site of simple bone cyst (76.9%) and its peak incidence was in the first and second decade (61.5%). Seven of 13 cases of simple bone cyst were seen pathological fracture and three of its cases were recurred. 6. In 13 cases of enchondroma, 6 cases were solitary and 7 cases were multiple lesions. The common site was phalanges of the hand and its peak incidence was in the second and third decade of life. 7. Giant cell tumor was 16 cases and to be divided into pathologically Grade 1 & 11 12 cases (75%) and Grade III 4 cases (25%). The sex distribution of giant cell tumor was 8 males and 8 females. The average age of giant cell tumor was 36.1 years with the peak incidence in the third and forth decade of life. 8. The average age of osteogenic sarcoma was 23.1 years with the peak incidence in the second decade of life. The sex distribution of osteogenic sarcoma was 25 males (54.3%) and 21 females (45.7%). The common sites of osteogenic sarcoma were distal femur and proximal tibia and proximal humerus in 41 cases (89.1%). 9. The average age of fibrosarcoma was 28.1 years with the peak incidence in the second and third decade of life. The sex distribution of fibrosarcoma was 12 males (66.6%) and 6 females (33.3%). The common site of fibrosarcoma were femur and tibia in 9 cases (50%). 10. Chondrosarcoma were 13 cases. The sex distribution of chondrosarcoma showed 5.5 times of the male predominence. The knee joint area was the most common site of chondrosarcoma (46.1%) and its peak incidence was in the third and forth decade of life.