Typical ester sulfates found in nature are sulfated mucopolysaccharides from animal sources and sulfated glycans from seaweeds. This article deals with the distribution, variation of chemical structures and functions of sulfated mucopolysaccharides, such as chondroitin sulfates A, C, D, E, K, dermatan sulfate and dermatan polysulfates, heparin, heparan sulfate and keratan sulfates.