The aim of this paper is to estimate Mesalazine or Mesalamine (MESA) in pharmaceuticals. The reversed-phase HPLC (RP-HPLC) results were used to evaluate the type of Mesalazine. Chromatographic analysis was carried out using an HPLC-UV method along with an Ion Pac column (Arcus EP-C18; 5 m, 4.6 mm, 250 mm) and a mobile phase of acetonitrile: acetic acid: water, 40:40:20 (v/v/v) + 0.5 M potassium dihydrogen orthophosphate buffer at pH 3.3, at a flow rate of 1.0 ml/min. At 260 nm, UV detection was employed in the HPLC method. Exactness, precision, particularity, linearity, and affectability were all accepted for the technique. The (MESA) had a maintenance time of (3.17) minutes. The (MESA) alignment plots were over the target ranges of 1-5 g/L, R2 0.9998. The quantitation limit was 0.3613 g/ml, with a detection limit of 1.636 g/ml. The precision of the proposed procedure, which ranged from 98.0 percent to 100 percent, was determined through recovery experiments. The modern HPLC-UV approach was used to analyze generic drug products, and the planned technique's efficiency was confirmed. The study's findings show that precision, accuracy, and efficiency are all within reasonable limits, so there is no substantial difference between the values obtained using the proposed methodology and those obtained using the traditional method.