The aim of this study was to validate a protocol for the determination of amlodipine besylate in capsules using the HPLC method with a DAD detector at a wavelength of 237 nm. The HPLC separation was carried out using a C18 column (25 cm × 4,6 mm
5 μm) and the mobile phase system was used as CH3OH and solution pH 3,0 (60:40) belonging to isocratic elution mode. The results of the validation proved that the method showed good selectivity, linearity with R2of 0,9997, a low limit of detection (LOD) of 1,27 ppm, a limit of quantification (LOQ) of 3,8 ppm, an accuracy of 100,02%, and a precision of the method (RSD) of less than 2%. In particular, the verified method was also applied to determine the amount of amlodipine besylate in three real samples on the market, and the results indicated that the content of amlodipinebesylate in all three preparations was above 94% and qualified as prescribed by the Vietnam Pharmacopoeia V.