Segmental cystic disease of the kidney is a rare form of cystic disease of the kidney that manifests as variable sized, numerous cysts that are localized in a segment of one kidney. Morphologically and pathologically, it is indistinguishable from autosomal dominant polycystic kidney disease except for its unilateral localization, the lack of an autosomal dominant genetic background and the progressive deterioration of the renal function. We experienced a case of surgically confirmed segmental cystic disease of the kidney in a 49-year-old patient and we report on its ultrasonographic and CT findings, along with a brief review of the relevant literature.