We developed a supercritical CO₂ extraction procession and determinated ginger essential oil contents from the ginger oleoresin to explore the effects of temperatures or pressures on the supercritical CO₂ extraction. Our research indicated that pressures had little effect on the liquid CO₂ extraction capacity. However, supercritical CO₂ extraction capacity was affected dramatically by the variant pressures. Additionally, changing pressures or temperature pushed the CO₂ into transcritical isolation state. Under this circumstance, we not only ensured the yield of ginger oleoresin, but also did we obtain the ginger essential oil and gingerol simultaneously.