Abstract: Taking Ganoderma lucidum in Northeast China as the experimental raw materials and the yield of Ganoderma triterpenes as the evaluation index, the extraction process by ultra-high pressure (UHP) and organic solvent extraction methods were optimized, and the antioxidant activity in vitro of Ganoderma triterpenes obtained by different extraction methods was studied. The optimum technology of assisted extraction by UHP was as follows: Pressure 350 MPa, solid-liquid ratio 1:20 g/mL, pressure holding time 7 min, ethanol concentration 90%, and the yield of triterpenoids was 1.154%. The optimum technology of organic solvent extraction was as follows: Solid-liquid ratio 1:25 g/mL, ethanol concentration 90%, extraction temperature 75 ℃, extraction time 3 h, and the yield of triterpenoids was 0.925%. The research results of antioxidant activity indicated: When the triterpenoids concentration extracted by UHP was 3 mg/mL, the free scavenging rates of DPPH and hydroxyl were respectively 59.64%±2.44%, 62.31%±1.57%, IC₅₀ was respectively 1.8 and 2.0 mg/mL, while the DPPH and hydroxyl free scavenging rates of the triterpenes extracted by organic solvent were only 41.87%±2.72% and 43.36%±2.36% under the same concentration conditions, and there was a good correlation between Ganoderma lucidum triterpene concentration and antioxidant activity. This study would lay the theoretical foundation for the extraction and application of Ganoderma lucidum triterpenes.