The physicochemical properties and in vitro biological activities of the polysaccharide from colloidal scale umbrella fungus were studied.The polysaccharide was prepared by aqueous extraction and alcohol pre-cipitation,and its physicochemical properties and antioxidant,anti-tumor,and blood glucose-lowering activi-ties were investigated.The results showed that the polysaccharide of colloidal scale umbrella fungus was mainly composed of glucose,mannose,xylose,and galactose.The extracted polysaccharide showed typical in-frared absorption peaks of polysaccharides,containing pyranoside and uronic acid,with the molecular weight of 29 754 Da.The extracted polysaccharide showcased scavenging activities against DPPH,hydroxyl,ABTS+,and superoxide anion free radicals and ferric ion reducing antioxidant power.In addition,the extracted polysaccha-ride inhibited the proliferation of BGC-823,HepG2,and Caco-2 cells and inhibited the activity of α-amylase.