Abstract:[Background] Pleurotus abieticola is a new species of edible and medicinal fungus with a potential economic value. [Objective] To well develop and utilize the polysaccharides in P. abieticola and develop potential functional foods. [Methods] The response surface methodology was employed to optimize the extraction process of P. abieticola polysaccharide. Furthermore, the in vitro antioxidant activities of the polysaccharide at different concentrations and Vc (positive control) were evaluated by measuring the activities in scavenging 1,1-diphenyl-2-picrylhydrazyl free radical (DPPH), 2,2'-azinobis-3-ethylbenzthiazoline-6-sulphonate (ABTS), hydroxyl radicals (·OH) and reducing iron ions. [Results] The extraction process was optimized as extraction at a liquid-to-solid ratio of 28.87:1 (mL:g) and 60.27℃ for 122.62 min, under which the extraction rate of pure polysaccharide from P. abieticola reached a maximum value of 2.39%. The polysaccharide at the concentration of 1 mg/mL showed the DPPH, ABTS, and ·OH scavenging rates of 49.42%, 88.37%, and 19.87%, respectively, and the iron ion reducing power of 0.273. [Conclusion] This study provides a theoretical basis for the efficient development and utilization of P. abieticola polysaccharide and lays a foundation for further research on the polysaccharide bioactivity and development of polysaccharide products.