The understanding of glycans, the third life chain, is widely desired. Naturally, the glycoconjugates are found in heterogeneous forms due to the enzyme competition in the same process. As a result, the synthesis of homogeneous glycans has become one of the trending research topics. In this review, orthogonal protection strategies were summarized to overcome the difficulties, such as the numerous hydroxyl groups of oligosaccharides and stereoselectivities during glycosylations. A variety of synthetic glycomics, including glycoproteins, glycolipids, and newly discovered glycoRNAs, were also presented. Their applications were categorized by different diseases, which elucidated the great potential of glycans as drug candidates in the next generation.