Hydrogel　wound　dressing　has　significant　advantages　in　wound　treatment.　It　can　shorten　the　time　of　wound　healing,　control　the　process　of　wound　healing,　and　effectively　promote　the　healing　of　damaged　tissues　in　a　hydrated　environment.　Sodium　alginate　(SA)　is　a　commonly　used　hydrogel　wound　dressing　material,　which　can　quickly　form　a　three-dimensional　network　structure　hydrogel　in　a　relatively　mild　environment,　but　the　mechanical　properties　and　stability　of　a　single　SA　hydrogel　are　poor.　The　composite　hydrogel　prepared　by　mixing　SA　with　other　substances　can　not　only　exert　the　performance　of　a　single　substance　but　also　improve　the　mechanical　properties,　stability　and　adsorption　of　the　hydrogel　and　has　a　wider　application　prospect　in　the　field　of　sustained　release　control　of　bioactive　substances.　Natural　polymers　have　been　widely　used　in　the　preparation　of　hemostatic　and　wound　healing　materials　due　to　their　excellent　biocompatibility,　degradability,　viscoelasticity　and　easy　processing.　This　paper　introduces　the　research　progress　of　composite　hydrogels　prepared　by　SA　and　natural　polymers　in　mechanical　properties,　antibacterial,　anti-inflammatory,　tissue　repair　and　sustained　release　control　of　bioactive　substances,　and　provides　a　theoretical　basis　for　the　application　of　SA-based　composite　hydrogels　in　wound　dressings.