Supercritical fluid extraction with a rectification process was developed with a view to separation of trace components from natural materials. Fundamental experiments for separation of 7-hydroxyflavone from anthracene were carried out in a newly developed apparatus at a pressure of 12 MPa. When the respective temperatures of supercritical CO2+ethanol extraction and rectification were controlled at 333 K and 353 K, and with a feed ethanol concentration of 12 mol% and a CO2 flow rate of 1.4 L/min, only anthracene was recovered from the top of the rectifier. Rectification conditions were optimized by selecting a low feed ethanol concentration and by taking into consideration the phase separation of CO2-ethanol systems.