A supercritical fluid extraction (SFE) method was developed for the extraction of paeonol in Paeonia suffruticosa Andr. and its patent preparations. A systematic method was used to optimize five variables (temperature, pressure, modifier concentration, static extracting time and CO2 dynamic extracting volume) of SFE. Sample extracts were analyzed by wide-bore capillary gas chromatography (CGC). The method showed good linearity (gamma = 0.9999) in the range of 0.1-1.6 mg.ml-1 of paeonol. The average recovery was 97.8% with RSD = 2.35% (n = 3) for Paeonia suffruticosa andr., 100.3% with RSD = 1.89% (n = 3) for its patent preparations.