Gardenia jasminoides flower has a good prospect as a raw material for cosmetics,but its development is limited due to the lack of research on it.In this study,the supercritical CO₂ extraction process of Gardenia jasminoides flower essential oil (GJFEO) and the ethanol ultrasonic extraction of Gardenia jasminoides flower flavonoids extract (GJFFE) in the residue were optimized through single factor investigation and orthogonal experiment.TheGardenia jasminoides flower compound extract (GJFCE) was then obtained by the mixture of GJFEO and GJFFE in proportion (mass ratio=1∶24).Afterwards,the antioxidant activities of GJFEO,GJFFE and GJFCE were investigated by cell experimentsin vitro.The results showed that the optimal extraction process for GJFEO was as follows:extraction temperature of 38 ℃,extraction pressure of 32 MPa,separation pressure of 12 MPa.The optimal extraction process for GJFFE was as follows:ethanol concentration of 50%,ratio of liquid to material of 25∶1,extraction twice,extraction time of 50 minutes.The three extracts had protective effects on HaCaT cells damaged by oxidation,and the antioxidant activity of GJFCE was better than that of GJFEO or GJFFE alone (P<0.001).This research provides technical support and theoretical basis for the deep processing of Gardenia jasminoides flower and its development in the field of cosmetics.