The document describes the development and validation of a HPLC method for the simultaneous quantification of Ambrisentan and Tadalafil in bulk and pharmaceutical formulations. The method utilizes an Inertsil C18 column with a mobile phase of buffer (pH 3):methanol (50:50) at a flow rate of 1 ml/min. Ambrisentan and Tadalafil were detected at 260 nm. The method was validated per ICH guidelines and was found to be linear, precise, accurate and robust for the analysis of Ambrisentan and Tadalafil without interference from excipients. The method can be used for the quality control of formulations containing these two drugs.