Abstract: Auricularia auricular is an edible and medicinal fungi. The amount of Auricularia auricular polysaccharide(AAP) is the highest in Auricularia auricular and it also is the most crucial functional components in it. Some significant biological functions of various AAPs and grading AAPs had been expounded systematically,including antioxidation,radioresistance,anticancer effection,immuno-enhancing,blood cholesterin-reducing,anticoagulation, anti-hyperglycemic and antiviral effection, and the corresponding experimental method and result of above biological functions are introduced. This paper will provide reference for further research and application of AAP.