Spondylocostal dysostoses are a group of rare inherited disease with a heterogeneous disorder of vertebral segmentation defects and rib anomalies, which lead to respiratory problems predicting the clinical outcome. Spiral CT with three-dimensional (3D) imaging provides exact measurement of the bony rib cage. We report a case of an infant with spondylothoracic dysostosis, a phenotype of spondylocostal dysostoses, and 3D spiral CT findings of his rib cage since it may contribute to the surgical planning.