Carbohydrates play essential roles in biological systems, where structural diversity and glycan-mediated interactions govern molecular recognition, immune responses, and tissue organization. These features provide a foundation for nature-inspired therapeutic design. In this review, we highlight how carbohydrate-based systems translate biological principles into functional therapeutic strategies. We focus on glycan-mediated immune activation, carbohydrate-based delivery systems, and polysaccharide biomaterials. Multivalent glycan architectures can directly activate innate immune pathways and remodel the tumor microenvironment, while plant-derived polysaccharides enable biologically responsive delivery through receptor recognition and microbiota-triggered release. At the materials level, polysaccharide-based hydrogels mimic extracellular matrices and support tissue regeneration. Together, these examples illustrate how carbohydrate-based design principles can be leveraged to develop next-generation precision therapeutics that integrate effectively with biological systems.