Authors analylsed 384 hips of 269 patients with osteonecrosis of the femoral head in adult, who were diagnosed and treated between August 1976 and March 1986 at the Department of ()rthopaedic Surgery, Kyung Hee University Hospital. These are investigated in terms of history, clinical data and reontgenogram, retrospectively. In 269 patients, nontraumatic femoral head necrosis (NTFHN) were 199 patients (74.0%) and traumatic femoral head necrosis (TFHN) were 70 patients (26.0%). The male was more affected in ratioof 3.1: 1, especially higher in NTFHN about 4: l. In alcohol-induced necrosis all were male patients, but in polyvinyl pyrrolidone(PVP)-storaged cases 63% were female patients. The peak incidence of age distribution was at 6th decade(average 53.9 years) in the TFHN ahd 5th decade(average 44.2 years) in NTFHN). The most frequent probable etiologic frctor in NTFHN was idiopathic (71 patients, 35.8%), followed by alcohol-induced (68 patients, 34.2%), steroid-induced (27 patients, 13.6%) and PVP-storaged (19 patients, 9.5%). The bilateral involvement in NTFHN was 112 patients (53.6%). The idiopathic cases (42.0%) were lower than steriod-induced (81.9%), alcohol-induced (76.5%) or PVP-storaged (63.2%) in the bilaterality. The associated diseases in NTFHN were hepatopathy (12 patients), diabetes (7 patients), pulmonary tuberculosis (6 patients) and dermatopathy (5 patients). And the underlying diseases in steroid-induced were nephrotic syndrome (4 patients), arthralgia (4 patiehts), rhematiod arthritis (3 patients), dermatopathy (4 patients) and systemic lupus erythematosus (1 patient). 61.4% of TFHN was diagnosed within 2 years after trauma, 56.7% of NTFHN had the duration of symptom over one year. The initial reontgenogram stage according to Ennekings classification was average stage 1V. In NTFHN cases, there were no significant relationship between etiologic factors and initial reotgenographic stage or duration of symptom. But there were significant corelation between Enneking’s reontgengraphic stage and clinical findings (range of movement of joint, Harris hip score, duration of symptom). In more severe cases than Enneking’s radiologic stage IV, Harris hip score not provide any information to select a proper treatment.