Abstract: The process of extracting essential oil from rose flowers(Rosa rugosa var.plena)using supercritical carbon dioxide was studied. Analysis results via orthogonal experiment and single-factor experiment were obtained. The results showed that the optimum extraction conditions were as follows: particle size 250μm, CO₂ circulation flow rate 25L/h, temperature 65℃ and pressure 20MPa. Under these conditions, the yield of rose essential oil can reach 5.225 7% The yield of essential oil was significantly affected by particle size, supercritical fluid flow rate, extraction temperature and pressure. The result also showed that, under the condition of small particle size, gas distributor could increase the yield effectively, which did not influence the fluid flow speed in the extraction vessel.

Key words: supercritical CO₂ extraction, rose, essential oil