This review provides a close look into the world leading cathodes-supported tubular solid oxide fuel cell (SOFC) technology. It starts from the basic facts of a SOFC, where the working principle, advantages, types and applications are specifically discussed. It then focuses on cathode-supported tubular SOFCs, one important branch of SOFCs, by providing detailed information on engineering innovations, materials advances, manufacturing processes and electrical performance of both traditional cylindrical and flattened ribbed tubular cells. The review ends with a high-level summary on the SOFC generator systems manufactured and demonstrated by Siemens/Westinghouse over the past half-century.