Carbohydrates play an essential role in the organism and have many bioactivities. Carbohydrate-based drug discovery is an up-and-coming area of research in medicinal chemistry. Bioactive carbohydrates open up a new source for drug development. More than 170 carbohydrate-based drugs have been successfully approved as anticoagulants, antitumor agents, antidiabetic agents, antibiotics, antiviral agents, and vaccines. However, most carbohydrates have low druggability. As such, new methods and strategies to improve carbohydrates' druggability are in high demand. This Special Issue aimed to serve as an open forum where researchers can share their experiences and findings on carbohydrate-based drugs, with a focus on the discovery and development of new carbohydrate-based therapeutic agents. Contributions to this issue, in the form of both original research and review articles, cover the separation, identification, synthesis, and pharmacology of bioactive carbohydrates, including monosaccharides, oligosaccharides, polysaccharides, glycopeptides, glycoproteins, glycomimetics, and others.