Abstract: With Chrysanthemum morifolium Ramat as the research object, supercritical CO2 as solvent, the β-elemene yield and volatile oil yield as measure indicators, the effects of four extraction parameters including particle diameter, extraction pressure, extraction temperature, extraction time on extraction processes were separately studied. Then it was optimized using orthogonal design based on single factor investigations for achieving higher β-elemene extraction yield and volatile oil extraction yield. Under the condition of particle diameter of 80 meshes, extraction pressure of 17.24 MPa, extraction temperature of 35℃, extraction time of100 min, the β-elemene yield was 104.57mg/kg and the volatile oil yield was 3.26%. It gave priority to β-elemene yield with due consideration to volatile oil yield with comprehensive index orthogonal design. It made process conditions more reasonable.