Abstract: 3-Deoxy-D-manno-2-octulosonic acid (Kdo) is a non-mammalian higher-carbon sugar, which is commonly found in the lipopolysaccharides and capsular polysaccharides of bacteria, and has been considered as a potential target for the development of antibacterial vaccines and diagnostic tools. In this review, we summarize the recent progress of Kdo glycosylation based on the types of the Kdo donors, and highlight the application of these glycosylation approaches in the synthesis of selected examples of complex Kdo oligosaccharides.