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The supercritical-fluid extraction of vitamins D2 and D3 with carbon dioxide is reported for the first time. The extraction recovery was enhanced by direct addition of diethyl ether to sample contained in the extraction cell. Separation and detection of the analytes was performed off-line by reversed-phase liquid chromatography with UV-detection. The quantification limit of the method is 4.1 μg for both analytes, with precision, expressed as relative standard deviation, of 3.8 and 6.3% for vitamins D2 and D3, respectively (η=7). The proposed method has been applied to the determination of vitamin D in different pharmaceutical products; recoveries were between 85 and 105%. [ABSTRACT FROM AUTHOR]