The contents of aloesin in aloe preparations were determined by HPLC. Aloesin was extracted 3 times with ethanol for 30 minutes. The ethanol extract was concentrated and suspend ed in saturated NaCl aqueous solution and successively partitioned with dichloromethane, n-butanol. Prepared samples were analyzed by HPLC on a reverse column(Inertsil ODS-2). In assay, internal standard was a puerarin and regression of calibration curve was 0.998. Recoveries of aloesin added to aloe preparation were 98~123(%).