The Computed tomography is a more accurate technique for detecting sclerotic bony change of osteitis condensans ilii than plain radiograph. We analysed a comparison between CT and plain radiograph of osteitis condensans ilii, a correlation between osteitis condensans ilii and women of childbearing age. The result were as follow. 1. The incidence of osteitis condensans ilii is 5.3% on KUB, 11.7% on CT when the width of iliac sclerosis is more than 7.5mm as diagnostic criteria. 2. We observed a osteitis condensans ilii between 19 years and 51 years of age, most frequently in fourth decade. 3. The width of iliac sclerosis is 10-13mm in 3 cases of osteitis condensans ilii in both CT& KUB, 7.5-9mm in 4 cases of osteitis condensans ilii on CT only. 4. The incidence of osteitis condensans ilii is increased significantly when the width of iliac sclerosis is less than 7.5mm as diagnostic criteria. 5. Relatively high correlation between osteitis condensans ilii and delivary in our stud (66.6%).