ABSTRACT: The development and validation  for  the  simultaneous  estimation  of  Sacubitril and Valsartan achieved by X-Terra  RP-18  (150mm*4.6mm,  5µm) column, with a mobile phase of 0.1% formic acid in water and Methanol (25:75% v/at a flow rate of 0.8ml/min at ambient temperature. The peaks  were observed  by  a UV-detector at 267nm  and  the  retention  time  for  both  the  drugs  was  3.156  and 2.663min. The percentage recovery was 99-100% for both the drugs. Method validation was carried out for all above new methods developed.  Linearity parameter for the method was analyzed by preparing solution of five levels of concentrations. Calibration curve for concentration versus peak areas was found linear. Precision was studied by preparing solutions in six replicates and analyzed, % RSD was calculated for the peak areas of each drug. Accuracy for new methods developed, evaluated by using the standard solutions of three  different  concentrations (50%, 100% and 150%) into sample solution and their percentage recovery at each  level  was  determined.  Robustness for above methods was carried out at different flow rates and at different organic composition, standard and sample solutions were prepared and analyzed at + 0.1ml/min and at + 10% and developed method found to be stable on deliberate variation. Parameters evaluated for validating novel RP-HPLC methods for simultaneous determination of above dosage forms meet the requirements of ICH guidelines. The developed methods are simple, precise, cost effective and rapid. These newly developed methods can be applied for the quantitative determination in the QC laboratories for the regular release.