During 5 years and 8 months, from September 1968 to May 1974, myelographic studies followed by operation were carried out on 118 cases of lumbar HIVD at Seoul National University Hospital. The myelographic findings and operative findings were analyzed and following conclusions were obtained. 1. The sex ratio was 75 males to 43 females. 2. Among the 118 cases, myelographic findings were consisted of the unilateral defect: 78 cases (67.0%), central defect: 30 cases (25.5%), and, bilateral defects: 10 cases (8.5%) respectively. 3. Among the 118 cases, the greastest incidence was L4-L5 disc space: 87 cases (73.7%) and next incidence was L5-S1 disc space: 25 cases (21.2%). 4. Among the 118 cases of lumbar herniated intervertebreal disc disease, the false positive was 8 cases (6.8%) and diagnostic accuracy of myelograpy was 91.5%. 5. Plain radiography has little value in diagnosis of lumbar herniated intervertebral disc disease among 118 cases, about 30% show significant sign in pl in film study.