Esomeprazole magnesium trihydrate (EMT) is a proton pump inhibitor used against peptic ulcer disease to suppress excess acid secretion in the st omach. Physico chemical characterization studies showed that EMT has showed a melting point of 177.33 0 C. The solubility of drug esomeprazole followed the order methanol>ethanol> a cetone> buufer pH 9.0 > distilled water. The analytical method developed for the estimation of esomeprazole magnesium trihydrate in bulk fluids showed maximum absorbance λ max of 203.5 nm in methanol between 200 nm and 400 nm. Linearity studies indicated that estimation of esomeprazole magnesium trihydrate between 2.00  g /ml to 10.00  g /ml was found to be linear with regression equati on of y = 0.1546*X - 0.00414; ( r 2 = 0.999). The method developed was validated for i nter and intra day variation, limit of quantitation studies. The SD values of Int er day and Intra day variation studies indicated that the variation is minimum. Limit of Quantitatio n of esomeprazole was found to be of 1.00  g /ml. The above analytical parameters indicated that the developed UV Spectrophotometric method of esomeprazole was simple, accurate and rep roducible.