In the last decade, polysaccharide hydrogels have been extensively used in the development of novel drug delivery systems. Their excellent biocompatible and biodegradation characteristics as well as their green origin make them an appealing resource for their implementation. In this chapter, we sum up various polysaccharide hydrogels of diverse nature, combined or not with other polymers or drug delivery systems, implemented in the delivery of biotherapeutics as proteins, growth factors, gene vector, enzymes, hormones or monoclonal antibodies, with a special focus on pharmaceutical and biotechnological fields.