Beyond the usual age of walking, the dysplasia of dislocated hip has become severe and its reversivility limited so that the reduced hip cannot maintained in stable position. The innominate osteotomy redirect cartilage of the hip and provide stability in the functional position of walking. The author have experienced 45 cases out of 42 patients with congenital dislocation of the hip who were treated by innominate osteotomy at Department of Orthopedic Surgery College of Medicine Yonsei University from Jan. 1979 to Dec. 1986. The analysis of result of operation has been Jan. 1979 at least 18 months follw-up study. 1. The mean age was 4.2 years ranging fron 18 months to 14 years.2. The mean value of parameters in preoperative evaluation, acetabular index was 37°, neck shaft angle 146°, CE angle −64° and leg length discrepency 1.5cm. After operation, actabular index was 20°, neck shaft angle 137° and CE angle 39° in average. And operated limb was longer as 0.5cm in average. 3. By anatomical assessment of NcKay, 17 cases were graded excellent, 19 cases good, 7 cases fair and 2 cases poor. Especially among the patients above 6 years old, only 6 cases were graded excellent or good. 4. As to the post-operative complication, limitation of motion was noted in 4 cases, redislocation in 2 cases, subluxation in 1 cases, avascular necrosis of femoral head in 1 case and infection in 1 case.