A fast,simple and sensitive high performance liquid chromatographic (HPLC) method has been developed for determination of 10α-methoxy-6-methyl ergoline-8β-methanol (MDL,a main metabolite of nicergoline) in human plasma.One-step liquid-liquid extraction (LLE) with diethyl ether was employed as the sample preparation method.Tizanidine hydrochloride was selected as the intal standard (IS).Analysis was carried out on a Diamonsil ODS column (150 mm × 4.6 mm,5 μm) using acetonitrile-ammonium acetate (0.1 mol/L) (15/85,v/v) as mobile phase at detection wavelength of 224 nm.The calibration curves were linear over the range of 2.288-73.2 ng/mL with a lower limit of quantitation (LLOQ) of 2.288 ng/mL.The intra- and inter-day precision values were below 13％ and the recoveries were from 74.47％ to 83.20％ at three qtality control levels.The method herein described was successfully applied in a randomized crossover bioequivalence study of two different nicergoline preparations after administration of 30 mg in 20 healthy volunteers.