To explore the effects of white Hypsizygus marmoreus polysaccharides on liver and kidney immunological activities of mice, we used them to establish a model for immunosuppressive mice which was induced by cyclophosphamide and determine related antioxidant indexes. We randomly divided sixty mice into normal control group, model group, positive control group, as well as high, medium and low refined polysaccharide from Hypsizygus marmoreus (RPHM) dosage group, to study the change of liver and kidney immune function by detecting the antioxidant indexes, including superoxide dismutase (SOD), GSH-Px activity, catalase (CAT) activity, glutathione and malondialdehyde (MDA) contents. The results showed that polysaccharides from white Hypsizygus marmoreus could significantly improve SOD activity, GSH content, GSH-Px activity, CAT activity(P<0.01) and decrease MDA content(P<0.01) , which imply that white Hypsizygus marmoreus polysaccharides have certain effects on enhancing the immune function of the immune-inhibited mice liver, while improving the immune regulation ability of kidney.