BACKGROUND: We aimed to clarify the iliac anatomy in developmental dysplasia of the hip using three-dimensional computed tomography. METHODS: The distance between two points along each anatomical portion of the ilium, including the acetabular center, were compared between patients in the dysplasia and control groups. RESULTS: There were no significant differences in the upper part of the ilium between the groups. However, three distances that included the acetabular center were significantly shorter in the dysplasia group than in the control group. CONCLUSIONS: Our study suggests that bone dysplasia occurs in the ilium near the acetabulum, not in the iliac wings.