Abstract:The nutritious function of Pleurotus geesteranus powder（GP）was studied.Forty C57BL/6 mice were randomized into four groups：normal control（NC）and low，medium-，and high-dose GP（GPL，GPM，and GPH，respectively）.The mice in the GP groups were administrated with corresponding doses of GP by gavage for 40 d.The results showed that compared with the NC group，the GPM and GPH groups showed lowered serum levels of alanine aminotransferase（ALT），blood urea nitrogen（BUN），and serum creatinine（Crea）.The three doses of GP lowered the levels of malondialdehyde（MDA）in the serum and kidney compared with the NC group.The GPM and GPH groups showed higher levels of serum superoxide dismutase（SOD）and live catalase（CAT）than NC group（P<0.05）.Furthermore，compared with the normal control，the GP groups exhibited enhanced glutathione peroxidase（GSH-Px）activity in the serum and kidney and increased thymus index.The GPH group had higher T lymphocyte stimulation index than the NC group.In addition，GP increased the relative abundance of Firmicutes，the number of OTUs，and the Alpha and Beta diversity of intestinal flora.In conclusion，GP could improve the intestinal flora and enhance the antioxidant activity and immunity in mice.