A reversed-phase high performance liquid chromatography (RP-HPLC) method was developed and validated for the estimation of esomeprazole in bulk and capsules dosage forms. The separation was achieved on C18 analytical column (250 mm × 4.6 mm i.d., 5.0 μm) using acetonitrile and phosphate buffer (pH 7.4 ± 0.05 adjusted with 5% potassium hydroxide) in the ratio 50:50 v/v as mobile phase and at a flow rate of 1.0 mL/min. Detection was carried out using a UV detector at 302nm. The total chromatographic analysis time per sample was about 7.0min with esomeprazole eluting at retention time of about 6.5min. The method was validated for accuracy, precision, specificity, linearity and sensitivity. Validation studies demonstrated that this HPLC method is simple, specific, rapid, reliable and reproducible. The standard curve was linear over the concentration range of 25-150μg/mL with R2 close to one (0.9991). The limit of detection (LOD) and limit of Quantitation (LOQ) obtained for esomeprazole were 0.015μg/mL and 0.04μg/mL, respectively. The developed and validated method was successfully applied for the quantitative analysis of Esoquin® capsules. The high recovery and low relative standard deviation confirm the suitability of the proposed method for the determination of esomeprazole in capsule dosage form.