Abstract: LC-MS/MS method was established for determination of amlodipine in human plasma. After protein precipitation of acetonitrile， the plasma sample was separated on an Eclipse XDB-C₁₈ column using methanol -1 mM ammonium acetate-0.1% formic acid as mobile phase by gradient elution. Detection was carried out by multiple reaction monitoring (MRM) on a 3200 Q-trap LC-MS/MS system. The assay was linear over the range 0.100—20.000 μg/L with a lower limit of quantitation of 0.100 μg/L. Intra-day and inter-day precision were less than 15%, respectively. The relative deviation was in the range -3.85%—1.94%. The recovery of amlodipine was in the range 94.90%—97.84%. The method is a rapid, sensitive, selective and reliable method for the determination of amlodipine in human plasma. The assay can be applied for the determination of amlodipine in human plasma and the study on pharmacokinetics of its preparation.