 Alginate is a natural polysaccharide that has been used extensively in biomedicine due to its excellent biocompatibility and biodegradability. It can be processed into three-dimensional scaffolds such as hydrogels, microspheres, microcapsules, sponges, foams and fibers, making it suitable for drug delivery and tissue engineering applications. Alginate-based biomaterials can also be modified by chemical and physical reactions to achieve desired properties such as tuned degradation rates, mechanical strength, dilation time and cell affinity. Recent research has focused on using alginates and their derivatives in tissue regeneration applications such as wound healing, cartilage repair, bone regeneration and drug delivery. This article was authored by Jinchen Sun and Huaping Tan.