RVP, a water-soluble triple-helix galactoglucomannan, was successfully extracted from the fruiting body of Russula virescens using an alkali extraction method. Physicochemical properties analysis showed that the protein content of RVP was low (0.95%). The main chain was mainly composed of 1,3,6-linked D-mannose and 1,6-linked glucose residues, and contained terminal glucose units and a small amount of 1,4-linked glucose and 1,6-linked galactose. The average molecular weight of RVP is approximately 8.91 ȕ 105, and it adopts a semi-rigid triple helix conformation. The antioxidant potential of RVP was initially assessed in vitro using H2O2 to induce oxidative stress in a cellular model, leading to cell damage and decreased survival rates. In comparison to the H2O2 model group, RVP exhibited substantial antioxidant activity, demonstrating a capacity to enhance cell viability in a concentration-dependent manner and notably reduce the level of malondialdehyde (MDA) in the cell supernatant, thus indicating its effectiveness in reducing lipid peroxidation. Furthermore, RVP was found to boost the activity of crucial antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) in the cells. Thus, RVP with antioxidant properties has broad application prospects in health and wellness.