Objective： To establish a liquid chromatography-mass spectrometry （LC-MS） method for determining the concentration of amlodipine besylate in human plasma and to evaluate the bioequivalence of 2 kinds of amlodipine besylate tablets. Methods： Twenty healthy male volunteers were enrolled into a single crossover study. A single dose of the suspension equivalent to 10 mg amlodipine besylate or a reference preparation was given in a crossover way. The plasma concentrations of amlodipine besylate were determined by LC-MS method in the volunteers at different time points; the pharmacokinetic parameters and relative bioavailability were calculated and the bioequivalence of the 2 preparations were evaluated. Results： The pharrnacokinetic parameters for experimental and the reference preparations were： Cmax （6. 21 ± 1. 88） vs（ 6. 03 ± 1. 08） ng/ml; AUC0-120（250. 68±52. 61） vs （246.14±52.11） ng h/ml; Tmax（6.0±2.3） vs （6. 1± 2.5） h; t1/2（40.45±6.68） vs （43.74±9.05） h, respectively. The linear range of the present method was 0. 1-20. 0 ng/ml; the lowest detectable concentration of amlodipine besylate was 0.1 ng/ml. There was no significant difference in pharmacokinetic parameters between the 2 tablets. Conclusion： The present method is simple to use, fast, and accurate. The 2 preparations of amlodipine besylate are bioequivalent.[