The authors performed clinical analysis upon 59 patients with acute suppurative osteomyelitis or septic arthritis who were admitted at our department from September, 1983 to June, 1989 and followed up for more than 1 year. The following results were obtained; l. Among 59 cases, 37 cases(62.7%) were male and 22 cases(37.3%) were female. The age of patients ranged from 10 days to 66 years, with the average age of 12.5 years. 2. Sites of involvement in acute osteomyelitis were femur in 15 cases(42.9%), tibia in 11 cases (31.4%) and in acute septic arthritis were hip joint in 12 cases(50.0%), knee joint in 10 cases (41.6%). 3. At the first visit, the average value of WBC counts was 13700/mm3 and that of ESR was 43mm/hr. In aspiration culture study, Staphylococcus aureus was isolated from 31 cases(52.5%), Gram(-) bacilli from 2 cases(3.4%), Hemophilus influenza from 1 case(1.7%), Proteus vulgaris from 1 case(1.7%), Salmonella paratyphi from 1 cases(1.7%) and negative culture was 23 cases(32.0%). 4. The average period between the onset of initial symptom and first visit to hospital was 6.4 days and the average duration of hospitalization was 18.7days. 5. Except 5 cases, 54 cases were treated by operative method, multiple bone drilling for acute osteomyelitis and irrigation and drainage for septic joint. 6. Four cases progressed to chronic osteomylitis radiologically, but only 2 cases showed clinical symptoms and remaining 2 cases were symptom free. Other complications were joint subluxation in 3 cases and concurrent pathologic fracture in 1 case, limb shortening in 1 case, angular deformity in 1 case, limited range of motion in 5 cases. The remaining cases showed excellent results with no recurrence as well as no abnormal radiological findings.